1.29: Harm reduction for people who use drugs- A life-saving opportunity
At the end of this case, students will be able to:
- Summarize how harm reduction improves the health of individuals and the community
- Identify best practices related to use of supportive language, provision of supplies for safer drug use, and connection to local harm reduction organizations
- Counsel a patient on harm reduction strategies and appropriate resources
Introduction
As defined by the Harm Reduction Coalition ® , harm reduction is “ a set of practical strategies and ideas aimed at reducing negative consequences associated with drug use .” 1 Harm reduction is a core component of the treatment model of substance use disorders (SUD), especially during ongoing substance use or when individuals do not identify abstinence as a primary goal. The most common misconception is that harm reduction is synonymous with promoting drug use. 1 Contrarily, harm reduction recognizes that substance use can be associated with significant harm, yet also recognizes that substance use has long been, and will continue to be, part of our world. 1 Instead, harm reduction represents a person-centered alternative to punitive and prohibitionist measures which lead to adverse health outcomes and social isolation. 1 While this ideology may sound like a novel concept, harm reduction strategies are utilized in many other areas of our lives such as seatbelts for cars, condoms for sex, and, most recently, face masks for COVID-19, for example. These interventions aim to reduce negative consequences associated with activities that impose some level of risk, such as driving a car, engaging in sex, or gathering with others during a viral pandemic. Though harm reduction in the context of substance use commonly targets people who inject drugs, people who use drugs via other routes can also benefit from harm reduction interventions.
Harm reduction for people who use drugs (PWUD) applies to a range of services personalized to the individual, substance(s) used, route(s) of use, and other risk factors. 2 These services are centered around overdose prevention, infection prevention, and social justice for PWUD in order to decrease morbidity and mortality. 2 Harm reduction interventions that decrease risk of overdose and death include strategies such as fentanyl test strips, administration of small initial test doses, using in the presence of others who are prepared to administer naloxone, taking turns and staggering use by at least 30 minutes, avoiding concomitant use of multiple central nervous system depressants, and using via a less dangerous route (e.g., intranasal rather than intravenous). 2 Harm reduction interventions to decrease risk of infectious diseases may include access to sterile syringes and other equipment, education to avoid reusing or sharing syringes, safer injection technique including location and step-by-step guide, administration of indicated vaccinations, HIV pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP), and provision of wound care. 2 Access to methadone and buprenorphine for alleviation of withdrawal and treatment of underlying opioid use disorder (OUD) has also been associated with reduced overdose and mortality risk, even when use of the medication is non-prescribed. 3-6 Use of these medications for treatment of OUD has also been shown to reduce risk for infectious disease. 7-16 Legal, policy, and regulatory changes are also essential to facilitate these harm reduction interventions; examples include naloxone access laws, overdose Good Samaritan laws, and removal of paraphernalia laws that impede syringe access. Harm reduction efforts to facilitate social justice for PWUD may go further to include public education, use of non-stigmatizing language, restructuring of SUD treatment models, decriminalizing substance possession and use, and addressing racial, gender, and sexual orientation inequities in SUDs.
Implementing harm reduction into pharmacy practice is imperative as the opioid overdose crisis continues to worsen alongside other concerning substance use trends. Overdose deaths related to opioids have continued to rise steadily despite annual decreases in opioid prescribing, driven primarily by potent synthetic opioid adulterants in the illegal drug supply. 17 Concerningly, polysubstance overdoses are also rising steeply with increased stimulant use, growing adulteration of the illegal benzodiazepine supply, and persistent concomitant use of alcohol. 18-19 The science associating harm reduction efforts with a positive impact on individual and public health is crystal clear. These interventions have been associated with higher uptake of SUD treatment, greater retention in care, fewer overdoses, safer injection practices, and greater viral suppression of transmittable diseases such as HIV and HCV. 20 Additionally, harm reduction is cost-effective, as it is estimated that syringe services programs cost $23 to $71 per person per year which are minimal when compared to the alternative medical costs of treating substance use and injection-related complications in addition to new HIV and HCV cases. 21 Lastly, harm reduction services are not associated with increased substance use, riskier substance use behavior, or increased crime in areas densely populated with harm reduction services. 22-24
Case
You are a pharmacy student on a community pharmacy advanced pharmacy practice experience (APPE) in a state where non-prescription syringe sales are legal.
CC: “I’d like to buy naloxone and a pack of syringes, please.”
Patient: The patient appears to be a non-Hispanic white male in their mid-20s. They use a wheelchair.
Interaction: You overhear a dialogue between the patient and one of the technicians at the pharmacy counter.
- Technician : “Do you have a prescription for those?”
- Patient : “No. I need 28 gauge, ½ inch, ½ mL, please.”
- Technician : “Well, what are the syringes for?”
- Patient : “Um, my grandmother. She has diabetes.”
- Technician : “Well, then she should have a prescription.”
- Patient : “Okay, well I do not have a prescription.”
- Technician : “And why do you need naloxone? That is for junkies.”
- Patient : “The naloxone is for a friend. Can I please just get these items? I can pay for them; they both really need them.”
- Technician : “No, I know what’s going on here. I am not selling you syringes to get high. You need to get clean.”
Case Questions
- What stigmatizing words were used in this interaction and how are these words harmful? What are their preferred alternatives?
- The patient appears distressed and begins to walk away from the pharmacy counter. You want to re-engage them in conversation and see how you can help. You approach them and offer to grab the intranasal naloxone and a pack of the syringes. You direct them to wait in the private consultation area while you grab the items. How would you establish rapport with this patient following their mistreatment by a member of the pharmacy staff?
- How would you counsel this patient on opioid overdose recognition and response, including proper use of intranasal naloxone?
- Now that you have re-engaged this patient and have openly discussed intranasal naloxone, you learn that they have only starting injecting substances within the past three months, but they share that they often reuse syringes which has led to irritation and infection in the past. At this point, how can you incorporate other harm reduction strategies into your conversation?
- What types of harm reduction services might you be able to offer this patient today?
- During your conversation, the patient expresses concern that they shared syringes with someone yesterday who may be HIV positive, but they are not sure and does not have a way of contacting this person. They are nervous, scared, and do not know what to do. How do you navigate this conversation?
Author Commentary
In community settings, pharmacists are rarely aware that they are interacting with a person who is using illegal or illegally-obtained drugs. If they are aware, that is often because they have identified a forged prescription or some other issue that is likely to lead to confrontation. Thus, a non-prescription syringe purchase presents a unique opportunity to engage with a person who may be at risk for harm related to illegal drug use without confrontation. A person who has progressed to injecting illegal drugs is unlikely to be in control of their drug use. The neurological changes associated with SUD are triggering a cycle of addiction that is not going to be interrupted by a pharmacist refusing to sell syringes. In the absence of sterile injection equipment, this patient will almost certainly reuse or share syringes. Additionally, carrying naloxone is encouraged not only for individuals who may be at risk of experiencing overdose, but also for individuals who may be likely to witness an overdose and thus be able to save a life. While a debate about whether pharmacists should sell syringes to someone they suspect of illegal drug use may be interesting in the context of an ethics class, the appropriate response is to sell the syringes. Pharmacists who refuse to do so, and institutions which establish policies that seek to prevent pharmacists from doing so, are acting in a manner that undermines public health. Furthermore, for pharmacists to truly provide a non-judgmental space to offer care for their patients, particularly related to harm reduction, it is very useful to reflect on their own experiences and exposure to narratives about substance use that may hinder their ability to be objective and offer patient care with compassion.
 Your family and friends want you to quit, you think about quitting often, and you have even been to inpatient treatment facilities a few times but always started using again eventually. You have been injecting for a few months using syringes given to you by a friend who obtained them from a syringe services program. You do not share, but you have been reusing and it is starting to hurt more when you inject. You decide to purchase some new syringes from the local pharmacy. You are anxious as you approach the counter. What if the pharmacist confronts you and asks why you need the syringes? What if they ask to see your arms to check for track marks? What if they loudly tell you to leave the store and talk about you later with other staff? As a pharmacist, what happens for this patient is up to you. Will you confirm their worst fears and risk discouraging them from ever purchasing sterile syringes from a pharmacy again, or will you embrace a harm reduction approach that protects their health? It is urged to choose the latter.
Patient Approaches and Opportunities
Pharmacists should recognize situations where naloxone should be offered and should utilize such opportunities to offer naloxone in a non-confrontational manner. In clinical practice, pharmacists may encounter less dramatic versions of this scenario where a patient asks for syringes, but does not request naloxone, despite your clinical intuition that they may benefit from it. In these types of scenarios, naloxone can be offered in a non-confrontational manner that does not make it about that person, such as informing them that this is an offering provided to all. This allows the patient to engage without the feeling that they may be implicitly admitting that their syringe purchase puts them at risk for an overdose. If the interaction goes well, and especially if the patient accepts the naloxone, it is helpful to close on a friendly note by inviting them to come back for a refill when needed, or if more questions arise. This will make the patient feel more comfortable returning and gives them some assurance when they can come in without fear of encountering a confrontational pharmacist.
Let the technicians and interns in your work environments know that you are comfortable selling syringes to anyone without a prescription or unnecessary hassle. Surveys indicate these individuals will typically follow the guidance of their supervisors on this topic. However, in the absence of guidance, they are likely to make the more conservative choice not to sell syringes to avoid reprimand. In addition to modeling supportive behaviors toward people who use drugs and enforcing a non-judgmental attitude among all staff, consider going further to educate colleagues by sharing resources designed to decrease stigma. 24
Related chapters of interest:
- Safe opioid use in the community setting: reverse the curse?
- Smoke in mirrors: the continuing problem of tobacco use
- A stigma that undermines care: opioid use disorder and treatment considerations
- PrEPare yourself: let’s talk about sex
- Alcohol use disorder: beyond prohibition
- Expanding the pharmacists’ role: assessing mental health and suicide
- Unintended consequences of e-cigarette use: a public health epidemic
External resources:
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IDU-related harm reduction and social justice action
- National Harm Reduction Coalition. https://harmreduction.org/issues/safer-drug-use/injection-safety-manual/
- Drug Policy Alliance. https://drugpolicy.org
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Naloxone training
- Narcan ® . https://www.narcan.com/patients/how-to-use-narcan
- Evzio ® . https://evzio.com/
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Non-stigmatizing language
- NIDA. https://www.drugabuse.gov/nidamed-medical-health-professionals/health-professions-education/words-matter-terms-to-use-avoid-when-talking-about-addiction
- The University of Texas at Austin Dell Medical School. Reducing Stigma Education Tools (ReSET). https://www.ResetStigma.org
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SUD treatment
- Crotty K, Freedman KI, Kampman KM. Executive summary of the focused update of the ASAM national practice guideline for the treatment of opioid use disorder. J Addict Med 2020;14:99-112.
- American Psychiatric Association. Practice guideline for the pharmacological treatment of patients with alcohol use disorder. 2018. https://psychiatryonline.org/doi/book/10.1176/appi.books.9781615371969
- Substance Abuse and Mental Health Services Administration and National Institute on Alcohol Abuse and Alcoholism. Medication for the treatment of alcohol use disorder: a brief guide. HHS Publication No. (SMA) 15-4907. Rockville, MD: Substance Abuse and Mental Health Services Administration, 2015.
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Finding MOUD providers and programs
- Substance Abuse and Mental Health Services Administration. https://www.samhsa.gov/medication-assisted-treatment/find-treatment
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Finding syringe services laws by state
- The Policy Surveillance Program. http://lawatlas.org/datasets/syringe-services-programs-laws
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Locating the nearest syringe services program
- North American Syringe Exchange Network. https://nasen.org/map/
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Harm reduction for pharmacists
- College of Psychiatric and Neurologic Pharmacists. https://cpnp.org/guideline/harmreduction
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Smokable drug use harm reduction
- Canadian Institute for Substance Use Research. https://www.heretohelp.bc.ca/sites/default/files/safer-smoking-crack-and-crystal-meth-2020.pdf
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Alcohol consumption harm reduction
- University of Washington, Harm Reduction Research and Treatment Center. https://depts.washington.edu/harrtlab/wordpress/wp-content/uploads/2018/11/Safer-Use-Alcohol.pdf
References
- National Harm Reduction Coalition. Principles of harm reduction. https://harmreduction.org/about-us/principles-of-harm-reduction/ . Accessed January 29, 2021.
- National Harm Reduction Coalition. Getting off right: a safety manual for injection drug users. https://harmreduction.org/drugs-and-drug-users/drug-tools/getting-off-right/ . Accessed January 29, 2021.
- Larochelle MR, Bernson D, Land T, et al. Medication for opioid use disorder after nonfatal opioid overdose and association with mortality: a cohort study. Ann Intern Med 2018;169(3):137-45.
- Wakeman SE, Larochelle MR, Ameli O, Chaisson CE, McPheeters JT, Crown WH, Azocar F, Sanghavi DM. Comparative effectiveness of different treatment pathways for opioid use disorder. JAMA Netw Open 2020;3(2):e1920622.
- Cicero TJ, Ellis MS, Chilcoat HD. Understanding the use of diverted buprenorphine. Drug Alcohol Depend 2018;193:117-23.
- Carlson RG, Daniulaityte R, Silverstein SM, Nahhas RW, Martins SS. Unintentional drug overdose: Is more frequent use of non-prescribed buprenorphine associated with lower risk of overdose? Int J Drug Policy 2020;79:102722.
- Sullivan LE, Moore BA, Chawarski MC, et al. Buprenorphine/naloxone treatment in primary care is associated with decreased human immunodeficiency virus risk behaviors. J Subst Abuse Treat 2008;35:87-92.
- Metzger DS, Donnell D, Celentano DD, et al; HPTN 058 Protocol Team. Expanding substance use treatment options for HIV prevention with buprenorphine-naloxone: HIV Prevention Trials Network 058. J Acquir Immune Defic Syndr 2015;68:554–61.
- Edelman EJ, Chantarat T, Caffrey S, et al. The impact of buprenorphine/naloxone treatment on HIV risk behaviors among HIV-infected, opioid-dependent patients. Drug Alcohol Depend 2014;139:79-85.
- MacArthur GJ, Minozzi S, Martin N, et al. Opiate substitution treatment and HIV transmission in people who inject drugs: systematic review and meta-analysis. BMJ 2012;345:e5945.
- Cohen MS, Chen YQ, McCauley M, et al; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med 2011;365:493–505.
- Montaner JSG, Lima VD, Barrios R, et al. Association of highly active antiretroviral therapy coverage, population viral load, and yearly new HIV diagnoses in British Columbia, Canada: a population-based study. Lancet 2010; 376:532-9.
- Wood E, Kerr T, Marshall BD, et al. Longitudinal community plasma HIV-1 RNA concentrations and incidence of HIV-1 among injecting drug users: prospective cohort study. BMJ 2009;338:b1649.
- Springer SA, Di Paola A, Azar MM, et al. Extended-release naltrexone improves viral suppression among incarcerated persons living with HIV with opioid use disorders transitioning to the community: results of a double-blind, placebo-controlled randomized trial. J Acquir Immune Defic Syndr 2018; 78:43-53.
- Springer SA, Qiu J, Saber-Tehrani AS, Altice FL. Retention on buprenorphine is associated with high levels of maximal viral suppression among HIV-infected opioid dependent released prisoners. PLoS One 2012; 7:e38335.
- US Centers for Disease Control and Prevention. Increase in fatal drug overdoses across the United States driven by synthetic opioids before and during the COVID-19 pandemic. https://emergency.cdc.gov/han/2020/han00438.asp . Accessed January 29, 2021.
- US Centers for Disease Control and Prevention. Other drugs. https://www.cdc.gov/drugoverdose/data/otherdrugs.html . Accessed January 29, 2021.
- Esser MB, Sherk A, Liu Y, et al. Deaths and years of potential life lost from excessive alcohol use – United States, 2011-2015. MMWR Morb Mortal Wkly Rep 2020;69(39):1428-33.
- Peckham AM, Young EH. Opportunities to offer harm reduction to people who inject drugs during infectious disease encounters: narrative review. Open Forum Infect Dis 2020;7(11):ofaa503.
- Wilson DP, Donald B, Shattock AJ, Wilson D, Fraser-Hurt N. The cost-effectiveness of harm reduction. Int J Drug Policy 2015;26 Suppl 1:S5-11.
- Kennedy MC, Karamouzian M, Kerr T. Public health and public order outcomes associated with supervised drug consumption facilities: a systematic review. Curr HIV/AIDS Rep 2017;14:161-83.
- Supervised Consumption Services. Drug policy alliance. https://www.drugpolicy.org/resource/supervised-consumption-services . Accessed January 29, 2021.
- Petrar S, Kerr T, Tyndall MW, et al. Injection drug users’ perceptions regarding use of a medically supervised safer injecting facility. Addict Behav 2007;32:1088–93.
- The University of Texas at Austin Dell Medical School. Reducing Stigma Education Tools (ReSET). https://www.ResetStigma.org . Accessed March 31, 2021.


30.1: Introduction
The structures of animals consist of primary tissues that make up more complex organs and organ systems. Homeostasis allows an animal to maintain a balance between its internal and external environments.
Homeostasis describes the dynamic balance of the body’s internal environment and the effort to maintain a constant, stable inside. There are many body components that contribute to homeostasis. Animals use homeostatic mechanisms to regulate things like pH, water and ion content, body temperature, blood pressure, and blood glucose. Not all animal bodies regulate all of these examples.
Animals vary in form and function. From a sponge to a worm to a goat, an organism has a distinct body plan that limits its size and shape. Animals’ bodies have evolved to interact with their environments, whether in the deep sea, a rainforest canopy, or the desert. Therefore, a large amount of information about the structure of an organism's body (anatomy) and the function of its cells, tissues and organs (physiology) can be learned by studying that organism's environment.
In lab we will be dissecting several animals in order to compare their anatomy and physiology.  The structure of an organism's body (anatomy) largely determines and limits the functionality (physiology) of that body. As you dissect animals in our lab, focus on the structures you are encountering and how they determine function. Consider what the role of that structure is in relation to other organs and how structures are put together into body systems.
We will see components and discuss functionality of the following systems:
- Integumentary System
- Musculoskeletal System
- Digestive System
- Circulatory System
- Respiratory System
- Nervous and Sensory Systems
- Reproductive and Endocrine Systems
- Osmoregulatory System
1. Integumentary System:
The integumentary system includes all coverings of the animal body. As you dissect animals in lab notice the different kinds of skin and integument and the structures that are derivatives of this system (hair and hair follicles, whiskers, bumps, horns, etc.).
2. Musculoskeletal System:
Muscle cells are specialized for contraction. Muscles allow for motions such as walking, and they also facilitate bodily processes such as respiration and digestion. The body contains three types of muscle tissue: skeletal muscle, cardiac muscle, and smooth muscle. Recall the differences in these three muscle types that you saw under the microscope.
Skeletal muscle tissue forms skeletal muscles, which attach to bones or skin and control locomotion and any movement that can be consciously controlled. Because it can be controlled by thought, skeletal muscle is also called voluntary muscle. Skeletal muscles are long and cylindrical in appearance; when viewed under a microscope, skeletal muscle tissue has a striped or striated appearance. The striations are caused by the regular arrangement of contractile proteins (actin and myosin). Actin is a globular contractile protein that interacts with myosin for muscle contraction. Skeletal muscle also has multiple nuclei present in a single cell.
Smooth muscle tissue occurs in the walls of hollow organs such as the intestines, stomach, and urinary bladder, and around passages such as the respiratory tract and blood vessels. Smooth muscle has no striations, is not under voluntary control, has only one nucleus per cell, is tapered at both ends, and is called involuntary muscle.
Cardiac muscle tissue is only found in the heart, and cardiac contractions pump blood throughout the body and maintain blood pressure. Like skeletal muscle, cardiac muscle is striated, but unlike skeletal muscle, cardiac muscle cannot be consciously controlled and is called involuntary muscle. It has one nucleus per cell, is branched, and is distinguished by the presence of intercalated disks.
A skeletal system is necessary to support the body, protect internal organs, and allow for the movement of an organism. There are three different skeleton designs that fulfill these functions: hydrostatic skeleton, exoskeleton, and endoskeleton.
Hydrostatic Skeleton
A hydrostatic skeleton is a skeleton formed by a fluid-filled compartment within the body, called the coelom. The organs of the coelom are supported by the aqueous fluid, which also resists external compression. This compartment is under hydrostatic pressure because of the fluid and supports the other organs of the organism. This type of skeletal system is found in soft-bodied animals such as sea anemones, earthworms, Cnidaria, and other invertebrates.
Exoskeleton
An exoskeleton is an external skeleton that consists of a hard encasement on the surface of an organism. For example, the shells of crabs and insects are exoskeletons. This skeleton type provides defence against predators, supports the body, and allows for movement through the contraction of attached muscles. As with vertebrates, muscles must cross a joint inside the exoskeleton. Shortening of the muscle changes the relationship of the two segments of the exoskeleton. Arthropods such as crabs and lobsters have exoskeletons that consist of 30–50 percent chitin, a polysaccharide derivative of glucose that is a strong but flexible material. Chitin is secreted by the epidermal cells. The exoskeleton is further strengthened by the addition of calcium carbonate in organisms such as the lobster. Because the exoskeleton is acellular, arthropods must periodically shed their exoskeletons because the exoskeleton does not grow as the organism grows.
Endoskeleton
An endoskeleton is a skeleton that consists of hard, mineralized structures located within the soft tissue of organisms. An example of a primitive endoskeletal structure is the spicules of sponges. The bones of vertebrates are composed of tissues, whereas sponges have no true tissues. Endoskeletons provide support for the body, protect internal organs, and allow for movement through contraction of muscles attached to the skeleton.
The human skeleton is an endoskeleton that consists of 206 bones in the adult. It has five main functions: providing support to the body, storing minerals and lipids, producing blood cells, protecting internal organs, and allowing for movement. The skeletal system in vertebrates is divided into the axial skeleton (which consists of the skull, vertebral column, and rib cage), and the appendicular skeleton (which consists of the shoulders, limb bones, the pectoral girdle, and the pelvic girdle).
3. Digestive System:
Animals obtain their nutrition from the consumption of other organisms. Depending on their diet, animals can be classified into the following categories: plant eaters (herbivores), meat eaters (carnivores), and those that eat both plants and animals (omnivores). The nutrients and macromolecules present in food are not immediately accessible to the cells. There are a number of processes that modify food within the animal body in order to make the nutrients and organic molecules accessible for cellular function. As animals evolved in complexity of form and function, their digestive systems have also evolved to accommodate their various dietary needs.
Herbivores, Omnivores, and Carnivores
Herbivores are animals whose primary food source is plant-based. Examples of herbivores include vertebrates like deer, koalas, and some bird species, as well as invertebrates such as crickets and caterpillars. These animals have evolved digestive systems capable of handling large amounts of plant material. Herbivores can be further classified into frugivores (fruit-eaters), granivores (seed eaters), nectivores (nectar feeders), and folivores (leaf eaters).
 The word carnivore is derived from Latin and literally means “meat eater.” Wild cats such as lions and tigers are examples of vertebrate carnivores, as are snakes and sharks, while invertebrate carnivores include sea stars, spiders, and ladybugs. Obligate carnivores are those that rely entirely on animal flesh to obtain their nutrients; examples of obligate carnivores are members of the cat family, such as lions and cheetahs. Facultative carnivores are those that also eat non-animal food in addition to animal food. Note that there is no clear line that differentiates facultative carnivores from omnivores; dogs would be considered facultative carnivores.
Omnivores are animals that eat both plant- and animal-derived food. In Latin, omnivore means to eat everything. Humans, bears, and chickens are example of vertebrate omnivores; invertebrate omnivores include cockroaches and crayfish.
Invertebrate Digestive Systems
Animals have evolved different types of digestive systems to aid in the digestion of the different foods they consume. The simplest example is that of a gastrovascular cavity and is found in organisms with only one opening for digestion. Platyhelminthes (flatworms), Ctenophora (comb jellies), and Cnidaria (coral, jelly fish, and sea anemones) use this type of digestion. Gastrovascular cavities are typically a blind tube or cavity with only one opening, the “mouth”, which also serves as an “anus”. Ingested material enters the mouth and passes through a hollow, tubular cavity. Cells within the cavity secrete digestive enzymes that break down the food. The food particles are engulfed by the cells lining the gastrovascular cavity.
The alimentary canal is a more advanced system: it consists of one tube with a mouth at one end and an anus at the other. Earthworms are an example of an animal with an alimentary canal. Once the food is ingested through the mouth, it passes through the esophagus and is stored in an organ called the crop; then it passes into the gizzard where it is churned and digested. From the gizzard, the food passes through the intestine, the nutrients are absorbed, and the waste is eliminated as feces, called castings, through the anus.
Vertebrate Digestive Systems
Vertebrates have evolved more complex digestive systems to adapt to their dietary needs. Some animals have a single stomach, while others have multi-chambered stomachs. Birds have developed a digestive system adapted to eating unmasticated food.
Monogastric: Single-chambered Stomach
As the word monogastric suggests, this type of digestive system consists of one (“mono”) stomach chamber (“gastric”). Humans and many animals have a monogastric digestive system. The process of digestion begins with the mouth and the intake of food. The teeth play an important role in masticating (chewing) or physically breaking down food into smaller particles. The enzymes present in saliva also begin to chemically break down food. The esophagus is a long tube that connects the mouth to the stomach. Using peristalsis, or wave-like smooth muscle contractions, the muscles of the esophagus push the food towards the stomach. In order to speed up the actions of enzymes in the stomach, the stomach is an extremely acidic environment, with a pH between 1.5 and 2.5. The gastric juices, which include enzymes in the stomach, act on the food particles and continue the process of digestion. Further breakdown of food takes place in the small intestine where enzymes produced by the liver, the small intestine, and the pancreas continue the process of digestion. The nutrients are absorbed into the blood stream across the epithelial cells lining the walls of the small intestines. The waste material travels on to the large intestine where water is absorbed and the drier waste material is compacted into feces; it is stored until it is excreted through the rectum.
Avian
Birds face special challenges when it comes to obtaining nutrition from food. They do not have teeth and so their digestive system must be able to process un-masticated food. Birds have evolved a variety of beak types that reflect the vast variety in their diet, ranging from seeds and insects to fruits and nuts. Because most birds fly, their metabolic rates are high in order to efficiently process food and keep their body weight low. The stomach of birds has two chambers: the proventriculus , where gastric juices are produced to digest the food before it enters the stomach, and the gizzard , where the food is stored, soaked, and mechanically ground. The undigested material forms food pellets that are sometimes regurgitated. Most of the chemical digestion and absorption happens in the intestine and the waste is excreted through the cloaca.
Parts of the Digestive System
The vertebrate digestive system is designed to facilitate the transformation of food matter into the nutrient components that sustain organisms.
Oral Cavity
The oral cavity, or mouth, is the point of entry of food into the digestive system. The food consumed is broken into smaller particles by mastication, the chewing action of the teeth. All mammals have teeth and can chew their food.
The extensive chemical process of digestion begins in the mouth. As food is being chewed, saliva, produced by the salivary glands, mixes with the food. Saliva is a watery substance produced in the mouths of many animals. There are three major glands that secrete saliva—the parotid, the submandibular, and the sublingual. Saliva contains mucus that moistens food and buffers the pH of the food. Saliva also contains immunoglobulins and lysozymes, which have antibacterial action to reduce tooth decay by inhibiting growth of some bacteria. Saliva also contains an enzyme called salivary amylase that begins the process of converting starches in the food into a disaccharide called maltose. Another enzyme called lipase is produced by the cells in the tongue. Lipases are a class of enzymes that can break down triglycerides. The lingual lipase begins the breakdown of fat components in the food. The chewing and wetting action provided by the teeth and saliva prepare the food into a mass called the bolus for swallowing. The tongue helps in swallowing—moving the bolus from the mouth into the pharynx. The pharynx opens to two passageways: the trachea, which leads to the lungs, and the esophagus, which leads to the stomach. The trachea has an opening called the glottis, which is covered by a cartilaginous flap called the epiglottis. When swallowing, the epiglottis closes the glottis and food passes into the esophagus and not the trachea. This arrangement allows food to be kept out of the trachea.
Esophagus
The esophagus is a tubular organ that connects the mouth to the stomach. The chewed and softened food passes through the esophagus after being swallowed. The smooth muscles of the esophagus undergo a series of wave like movements called peristalsis that push the food toward the stomach. The peristalsis wave is unidirectional—it moves food from the mouth to the stomach, and reverse movement is not possible. The peristaltic movement of the esophagus is an involuntary reflex; it takes place in response to the act of swallowing.
A ring-like muscle called a sphincter forms valves in the digestive system. The gastro-esophageal sphincter is located at the stomach end of the esophagus. In response to swallowing and the pressure exerted by the bolus of food, this sphincter opens, and the bolus enters the stomach. When there is no swallowing action, this sphincter is shut and prevents the contents of the stomach from traveling up the esophagus. Many animals have a true sphincter; however, in humans, there is no true sphincter, but the esophagus remains closed when there is no swallowing action. Acid reflux or “heartburn” occurs when the acidic digestive juices escape into the esophagus.
Stomach
A large part of digestion occurs in the stomach. The stomach is a saclike organ that secretes gastric digestive juices. The pH in the stomach is between 1.5 and 2.5. This highly acidic environment is required for the chemical breakdown of food and the extraction of nutrients. When empty, the stomach is a rather small organ; however, it can expand to up to 20 times its resting size when filled with food. This characteristic is particularly useful for animals that need to eat when food is available.
The stomach is also the major site for protein digestion in animals other than ruminants. Protein digestion is mediated by an enzyme called pepsin in the stomach chamber. Pepsin is secreted by the chief cells in the stomach in an inactive form called pepsinogen . Pepsin breaks peptide bonds and cleaves proteins into smaller polypeptides; it also helps activate more pepsinogen, starting a positive feedback mechanism that generates more pepsin. Another cell type—parietal cells—secrete hydrogen and chloride ions, which combine in the lumen to form hydrochloric acid, the primary acidic component of the stomach juices. Hydrochloric acid helps to convert the inactive pepsinogen to pepsin. The highly acidic environment also kills many microorganisms in the food and, combined with the action of the enzyme pepsin, results in the hydrolysis of protein in the food. Chemical digestion is facilitated by the churning action of the stomach. Contraction and relaxation of smooth muscles mixes the stomach contents about every 20 minutes. The partially digested food and gastric juice mixture is called chyme . Chyme passes from the stomach to the small intestine. Further protein digestion takes place in the small intestine. Gastric emptying occurs within two to six hours after a meal. Only a small amount of chyme is released into the small intestine at a time. The movement of chyme from the stomach into the small intestine is regulated by the pyloric sphincter.
When digesting protein and some fats, the stomach lining must be protected from getting digested by pepsin. There are two points to consider when describing how the stomach lining is protected. First, as previously mentioned, the enzyme pepsin is synthesized in the inactive form. This protects the chief cells, because pepsinogen does not have the same enzyme functionality of pepsin. Second, the stomach has a thick mucus lining that protects the underlying tissue from the action of the digestive juices. When this mucus lining is ruptured, ulcers can form in the stomach. Ulcers are open wounds in or on an organ caused by bacteria ( Helicobacter pylori ) when the mucus lining is ruptured and fails to reform.
Small Intestine
Chyme moves from the stomach to the small intestine. The small intestine is the organ where the digestion of protein, fats, and carbohydrates is completed. The small intestine is a long tube-like organ with a highly folded surface containing finger-like projections called the villi . The apical surface of each villus has many microscopic projections called microvilli. These structures are lined with epithelial cells on the luminal side and allow for the nutrients to be absorbed from the digested food and absorbed into the blood stream on the other side. The villi and microvilli, with their many folds, increase the surface area of the intestine and increase absorption efficiency of the nutrients. Absorbed nutrients in the blood are carried into the hepatic portal vein, which leads to the liver. There, the liver regulates the distribution of nutrients to the rest of the body and removes toxic substances, including drugs, alcohol, and some pathogens.
The human small intestine is over 6m long and is divided into three parts: the duodenum, the jejunum, and the ileum. The “C-shaped,” fixed part of the small intestine is called the duodenum . The duodenum is separated from the stomach by the pyloric sphincter which opens to allow chyme to move from the stomach to the duodenum. In the duodenum, chyme is mixed with pancreatic juices in an alkaline solution rich in bicarbonate that neutralizes the acidity of chyme and acts as a buffer. Pancreatic juices also contain several digestive enzymes. Digestive juices from the pancreas, liver, and gallbladder, as well as from gland cells of the intestinal wall itself, enter the duodenum. Bile is produced in the liver and stored and concentrated in the gallbladder. Bile contains bile salts which emulsify lipids while the pancreas produces enzymes that catabolize starches, disaccharides, proteins, and fats. These digestive juices break down the food particles in the chyme into glucose, triglycerides, and amino acids. Some chemical digestion of food takes place in the duodenum. Absorption of fatty acids also takes place in the duodenum.
The second part of the small intestine is called the jejunum . Here, hydrolysis of nutrients is continued while most of the carbohydrates and amino acids are absorbed through the intestinal lining. The bulk of chemical digestion and nutrient absorption occurs in the jejunum.
The ileum is the last part of the small intestine and here the bile salts and vitamins are absorbed into blood stream. The undigested food is sent to the colon from the ileum via peristaltic movements of the muscle. The ileum ends and the large intestine begins at the ileocecal valve. The vermiform, “worm-like,” appendix is located at the ileocecal valve. The appendix of humans secretes no enzymes and has an insignificant role in immunity.
Large Intestine
The large intestine reabsorbs the water from the undigested food material and processes the waste material. The human large intestine is much smaller in length compared to the small intestine but larger in diameter. It has three parts: the cecum, the colon, and the rectum. The cecum joins the ileum to the colon and is the receiving pouch for the waste matter. The colon is home to many bacteria or “intestinal flora” that aid in the digestive processes. The colon can be divided into four regions, the ascending colon, the transverse colon, the descending colon and the sigmoid colon. The main functions of the colon are to extract the water and mineral salts from undigested food, and to store waste material. Carnivorous mammals have a shorter large intestine compared to herbivorous mammals due to their diet.
Rectum and Anus
The rectum is the terminal end of the large intestine. The primary role of the rectum is to store the feces until defecation. The feces are propelled using peristaltic movements during elimination. The anus is an opening at the far-end of the digestive tract and is the exit point for the waste material. Two sphincters between the rectum and anus control elimination: the inner sphincter is involuntary and the outer sphincter is voluntary.
Accessory Organs
The organs discussed above are the organs of the digestive tract through which food passes. Accessory organs are organs that add secretions (enzymes) that catabolize food into nutrients. Accessory organs include salivary glands, the liver, the pancreas, and the gallbladder. The liver, pancreas, and gallbladder are regulated by hormones in response to the food consumed.
The liver is the largest internal organ in humans and it plays a very important role in digestion of fats and detoxifying blood. The liver produces bile, a digestive juice that is required for the breakdown of fatty components of the food in the duodenum. The liver also processes the vitamins and fats and synthesizes many plasma proteins.
The pancreas is another important gland that secretes digestive juices. The chyme produced from the stomach is highly acidic in nature; the pancreatic juices contain high levels of bicarbonate, an alkali that neutralizes the acidic chyme. Additionally, the pancreatic juices contain a large variety of enzymes that are required for the digestion of protein and carbohydrates.
The gallbladder is a small organ that aids the liver by storing bile and concentrating bile salts. When chyme containing fatty acids enters the duodenum, the bile is secreted from the gallbladder into the duodenum.
Liver
The liver is an organ within the digestive system and is responsible for maintaining sugar levels in the blood as part of homeostasis. After a large meal, the liver converts extra glucose into glycogen , a polysaccharide that stores glucose. A hormone called insulin is produced by the pancreas stimulates glycogen production. When levels of glucose in the blood drop, the liver breaks down glycogen back into glucose for the blood to circulate throughout the body. A hormone called glucagon produced by the pancreas stimulates this process. All cells of the body require glucose for cellular respiration to make energy.
The liver receives blood from the small intestines through the hepatic portal vein . After a large meal, the hepatic vein would transport glucose rich blood from the small intestines to the liver. Blood leaves the liver and returns to the heart through the hepatic vein .
4. Circulatory System:
The cardiovascular system has three major jobs in most animals
-
Transport
- Gases (Oxygen, carbon dioxide)
- Nutrients to cells
- Metabolic wastes
- Water
- Hormones
- Homeostasis
-
Protection
- Blood clotting factors
- White blood cells to fight against infection
Some invertebrates (like cnidarians) rely on a gastrovascular cavity for these functions, or diffuse gases and metabolic wastes directly through their skin. Larger and more complex animals have open or closed circulatory systems. In closed circulatory systems, the blood or equivalent transport medium is entirely within vessels in the body. Humans, other vertebrates, and squid have closed circulatory systems. In open circulatory systems, like those found in insects and many other invertebrates, blood circulates through vessels and open sinuses and can mix with interstitial fluid (this mix is called hemolymph).
Circulatory systems typically require a pump, also known as the heart, to contract and push the fluid around the body. Many animals have more than one heart for this purpose.
5. Respiratory System:
Exchange of oxygen and carbon dioxide requires a wet, thin surface for diffusion to occur. Respiratory surfaces may be internal (lungs) or external (gills) and depend on the animals environment. Small animals in wet environments can have thin skin for direct cutaneous respiration.
6. Nervous and Sensory Systems:
Nervous systems are unique to animals and are critical for detecting and interpreting information, making decisions, and regulating body functions and movements. Nervous systems are constructed from neurons and glia. Neurons are the main functional cells while glia play a variety of support roles.
Nervous systems develop as interconnected networks of cells. The largest nervous organs are the brains of vertebrates, while animals as simple as jellyfish have a ‘nerve net’. A critical concept related to nervous systems is consciousness, or ‘self-awareness’. That idea will be discussed from one perspective in the next lab, distinguishing sensation from perception.
The exercises here will review cellular function and structure, and explore several basic neural networks within the larger body. We will use a combination of models and microscopic analysis, gross anatomical dissection, and physiological exercises to study nervous systems. An overview of the components of nervous systems.
Overview of the Components of Nervous Systems:
| Cellular Components | |
|---|---|
| Cell Structures | Cell Functions |
Neurons:
|
|
Glia (or glial cells, or neuroglia):
|
|
The essential component is neurons, the major functional cells in nervous tissue. In many sensory organs, additional cells and tissues will contribute to the process of signal transduction.
Signal transduction is the process of a receptor detecting specific forms of matter or energy, and activating chemical and electrical changes in neurons. The neurons can then communicate with other neurons in the nervous system via synapses and networks to coordinate responses.
Receptor is a term used for the part of a sensory organ that detects the signal. ‘Receptor’ can refer to specific protein molecules which first interact with the matter or energy, the cell(s) that contains those proteins, or an assembly of cells in the larger organ.
Sensory Organs:
The major sensory organs can be grouped based on various characteristics, i.e. what type of matter or energy they detect and subsequently ‘transduce’ to produce our perceptions (e.g. vision, taste). Eventually, there are electrical and chemical signals within our brains. Specific organs include:
| Sensory Organ (Major Receptor) | Matter/Energy Detected By Receptor | General Anatomy and Physiology | Perceived Sensation |
|---|---|---|---|
| Eye (Retina) | Visible light (Electromagnetic Radiation) | Multilayered nervous sheet within the eye with muscles and lenses for focusing | Vision |
| Ear (Cochlea) | Physical force (Sound) | Flexible ‘hair’ cells that release signal molecules based on waves in fluid started by the motion of the eardrum | Hearing |
| Ear (Semicircular Canals, Saccule, Utricle) | Physical Force | Flexible ‘hair’ cells that release signal molecules based on waves in fluid started by the motion of the head | Movement |
| Nose (Olfactory Epithelium) | Chemicals (‘Odorants’) | A layer of neurons at the top of the nasal cavity | Smell (’Olfaction’) |
| Tongue (Taste Buds) | Chemicals | Clusters of epithelial cells that release signals to neurons if specific chemicals are present (e.g. sodium ions) | Taste (‘Gustation’) |
| Skin (Mechanoreceptors) | Physical Force | Various neurons that respond to physical movements | Touch |
| Skin (Thermoreceptors) | Heat Transfer | Specific neurons that respond to increases in temperature | Hot |
| Skin (Thermoreceptors) | Heat Transfer | Specific neurons that respond to decreases in temperature | Cold |
| Muscles & Tendons | Physical Force | Neurons responding to stretch and contraction of muscles & tendons | Body Position (Proprioception) |
| Most of the body | Various Signals | Neurons responding to physical force, temperature, and specific chemicals to warn of (potential) damage. | Pain (‘Nociception’) |
In order to investigate and understand sensory processes, we will investigate their anatomical structures (at macro- and microscopic levels) and physiological functions. An important distinction to consider is how humans can functionally separate sensation (activation of the different receptors) as compared to perception (the conscious awareness of the sensation). This distinction reveals how sensory deficits can result from damage in brain regions, even though the sensory organ is intact. Also, we may have perceptions that are only present in the brain, even though the sensory organs are silent.
7. Reproductive and Endocrine Systems:
Animal reproduction is necessary for the survival of a species. In the animal kingdom, there are innumerable ways that species reproduce. Asexual reproduction produces genetically identical organisms (clones), whereas in sexual reproduction, the genetic material of two individuals combines to produce offspring that are genetically different from their parents.
Generally, the producers of sperm (the small gamete) are called males, producers of the eggs (the large gamete) are called females. Any other characteristics that may often be associated with sex, such as chromosomes, parental care, or sexual behavior, are not universal throughout the animal kingdom. During sexual reproduction the male gamete (sperm) may be placed inside the female’s body for internal fertilization, or the sperm and eggs may be released into the environment for external fertilization.
Various internal and external structures allow animals to reproduce, including gonads, tubules to allow gametes to exit the body, and external structures for gamete deposition or transfer.
Many reproductive organs (like gonads) are also endocrine organs, and reproduction is one of the major processes the endocrine system controls. The endocrine system is the system that produces hormones, which are chemicals the body uses to communicate between organs and systems and control major processes like reproduction, growth, metabolism, and the stress response (and many more!). Many organs that are part of other systems produce hormones (like the gonads, pancreas, and brain) and there are some glands specific to the endocrine system (thyroid, pituitary, pineal). Glands are often hard to find in dissections as they tend to be small and soft and difficult to differentiate from other tissue.
8. Osmoregulatory System:
Kidneys
The kidneys are part of the urinary system. As they produce urine to release nitrogenous wastes from the body the kidneys also maintain homeostasis through pH balance and water-salt balance in osmoregulation . These bean shaped organs are located along the dorsal wall of the abdominal cavity.
Observe the kidney models available in the lab. Locate the outer renal cortex tissue and the more internal renal medulla. The renal pelvis is the area that collects the urine. Find the renal artery and the renal vein.
The functioning unit of the kidney is called the nephron. Part of the nephron is located in the cortex and part in the medulla. Use the picture below and the models in the lab to identify the following components of the nephron.
- Glomerulus
- Bowman’s capsule
- Proximal tubule
- Distal tubule
- Loop of Henle (descending limb and ascending limb)
- Collecting duct
- Peritubular capillaries
Urine production in the kidney involves four main steps:
- Filtration : molecules move out of the glomerulus into Bowman’s capsule. Large molecules like proteins and blood cells are too big to be filtered and remain in the blood.
- Reabsorption : glucose and amino acids move from the proximal tubule back into the blood stream through peritubular capillaries.
- Secretion : Substances like histamines, H+, and ammonia get secreted into the nephron from the peritubular capillaries
- Water reabsorption : both the Loop of Henle and the collecting duct reabsorb water to maintain the blood volume
Kidneys are also important in osmoregulation , maintaining an internal salt/water balance. The kidney can produce large amounts of dilute urine or small amounts of concentrated urine depending on the needs of the body. The pituitary glad produces antidiuretic hormone (ADH) which controls the concentration of urine output. ADH specifically acts on the collecting duct making it more or less permeable to water. Kidneys also play a role in pH balance.
LICENSES AND ATTRIBUTIONS
CC LICENSED CONTENT, SHARED PREVIOUSLY
- Biology 102 Labs. Authored by : Lynette Hauser. Provided by : Tidewater Community College. Located at : [www.tcc.edu] . License : CC BY: Attribution


6.3: Music of Franz Schubert (1797-1828)
Franz Schubert lived a short but prolific musical life. Like Joseph Haydn, he performed as a choirboy until his voice broke. He also received music lessons in violin, piano, organ, voice and musical harmony: many of his teachers remarked on the young boy’s genius. Schubert followed in his father’s footsteps for several years, teaching school through his late teens, until he shifted his attention to music composition fulltime in 1818. By that time he had already composed masterpieces for which he is still known, including the German Lied , Der Erlkönig (in English, The Erlking ), which we will discuss.Schubert spent his entire life in Vienna in the shadow of the two most famous composers of his day: Ludwig van Beethoven, whose music we have already discussed, and Gioachino Rossini, whose Italian operas were particularly popular in Vienna in the first decade.
Inspired by the music of Beethoven, Schubert wrote powerful symphonies and chamber music, which are still played today; his “Great” Symphony in C major is thought by many to be Schubert’s finest contribution to the genre. He wrote the symphony in 1825 and 1826, but it remained unpublished and indeed perhaps unperformed until Robert Schumann discovered it in 1838. Schumann famously remarked on the “heavenly length” of this composition that can take almost an hour to per- form. One reason for its length is its melodic lyricism, although the symphony also reflects the motivic developmental innovations of Beethoven.
Schubert also wrote operas and church music. His greatest legacy, however, lies in his more than 600
Lieder,
or art songs. His songs are notable for their beautiful melodies and clever use of piano accompaniment and bring together poetry and music in an exemplary fashion. Most are short, stand alone pieces of one and a half to five minutes in length, but he also wrote a couple of song cycles. These songs were published and performed in many private homes and, along with all of his compositions, provided so much entertainment in the private musical gatherings in Vienna that these events were renamed as Schubertiades (see the famous depiction of one Schubertiade by the composer’s close friend Moritz Schwind (painted years after the fact from memory in 1868). Many of Schubert’s songs are about romantic love, a perennial song top- ic. Others, such as
The Erlking
, put to music romantic responses to nature and to the supernatural.
The Erlking
is strikingly dramatic, a particular reminder that music and drama interacted in several nineteenth-century genres, even if their connections can be most fully developed in a lengthy composition, such as an opera.
Focus Composition:
Schubert, The Erlking (1815)
Schubert set the words of several poets of his day, and The Erlking (1815) is drawn from the poetry of the most famous: Johann Wolfgang von Goethe. The Erlking tells the story of a father who is rushing on horseback with his ailing son to the doctor. Delirious from fever, the son hears the voice of the Erlking, a grim reap- er sort of king of the fairies, who appears to young children when they are about to die, luring them into the world beyond. The father tries to reassure his son that his fear is imagined, but when the father and son reach the courtyard of the doctor’s house, the child is found to be dead.
As you listen to the song, follow along with its words. You may have to listen several times in order to hear the multiple connections between the music and the text. Are the ways in which you hear the music and text interacting beyond those pointed out in the listening guide?
|
Listening Guide For audio, go to: https://www.youtube.com/watch?v=5XP5RP6OEJI Performed by baritone Dietrich Fischer Dieskau and pianist Gerald Moore. |
| Composer: Franz Schubert |
| Composition: The Erlkönig (in English, The Erlking ) |
| Date: 1815 |
| Genre: art song |
| Form: through-composed |
|
Nature of Text: Original Text
Wer reitet so spät dur ch Nacht und Wind? Es ist der Vater mit seinem Kind.
Mein Sohn, was birgst du so bang dein Gesicht? Siehst Vater, du den Erlkönig nicht!
Du liebes Kind, komm geh’ mit mir!
Mein Vater, mein Vater, und hörest du nicht, Was Erlenkönig mir leise verspricht?
Willst feiner Knabe du mit mir geh’n?
Mein Vater, mein Vater, und siehst du nicht dort Erlkönigs Töchter am düsteren Ort?
Ich lieb dich, mich reizt deine schöne Gestalt, Und bist du nicht willig, so brauch ich Gewalt! Mein Vater, mein Vater, jetzt faßt er mich an, Erlkönig hat mir ein Leids getan. Dem Vater grauset’s, er reitet geschwind, Er hält in den Armen das ächzende Kind, Erreicht den Hof mit Mühe und Not, In seinen Armen das Kind war tot. Translation: Who rides there so late through the night and
wind?
“My son, why do you anxiously hide your face?” “Look, father, is it not the Erlking!

“My father, my father, and do you not see,
“I love you, I’m charmed by your lovely form! And if you’re unwilling, then force I’ll employ.” “My father, my father, he seizes me fast,
The father, horrified, rides quickly,
|
| Performing Forces: solo voice and piano |
|
What we want you to remember about this composition:
|
||
|
Other things to listen for:
|
| Timing | Performing Force, Melody and Texture | Text and Form |
| 0:00 |
Piano introduction
Opens with a fast tempo melody that begins low in the register, ascends through the minor scale, and then falls. Accompanied by repeat- ed triplet octaves. The ascending/ descending melody may represent the wind. The minor key suggests a serious tone. The repeated octaves using fast triplets may suggest the running horse and the urgency of the situation. |
|
| 0:24 |
Voice and piano from here to the end; Performing forces are voice and piano in homophonic texture from here to the end. Melody falls in the middle of the singer’s range and is accompanied by the repeated octave triplets. |
Narrator:
Who rides so late through night and wind? |
|
0:56 |
Melody drops lower in the singer’s range. |
Father:
|
| 1:03 | Melody shifts to a higher range | Son: Do you see the Erlking, father? |
| 1:19 | Melody lower in range. |
Father:
It is the fog. |
|
1:28 |
The key switches to major, perhaps to suggest the friendly guise assumed by the Erlking. Note also the softer dynamics and lighter arpeggios in the piano accompaniment |
The Erlking:
|
|
1:52 |
Back in minor the melody hovers around one note high in the singer’s register; the minor mode reflects the son’s fear, as does the melody, which repeats the same note, almost as if the son is unable to sing another |
Son:
|
|
2:03 |
Melody lower in range |
Father:
|
|
2:13 |
Back to a major key and piano dynamics for more from the Erlking |
The Erlking:
|
|
2:30 |
Back to a minor key and the higher-ranged melody that hovers around one pitch for the son’s retort. |
Son:
|
|
2:41 |
Melody lower in range and return of the louder repeated triplets |
Father:
|
|
2:58 |
Momentarily in major and then back to minor as the Erlking threatens the boy |
The Erlking:
|
|
3:09 |
Back to a minor key and the higher-ranged melody that hovers around one pitch. |
Son:
|
|
3:22 |
Back to a mid-range melody; the notes in the piano get faster and louder. |
Narrator: The father, filled with horror, rides fast |
|
3:37 |
Piano accompaniment slows down; dissonant and minor chords pervasive; song ends with a strong cadence in the minor key; Slowing down of the piano accompaniment may echo the slowing down of the horse. The truncated chords and strong final minor chords buttress the announcement that the child is dead. |
Narrator: They arrive at the courtyard. In his father’s arms, the child was dead. |
The next generation of nineteenth-century composers—born in the first two decades of the century—included a number of talented pianists: Felix and Fanny Mendelssohn, Robert and Clara Schumann, Fryderyk Chopin, and Franz Liszt. They were joined by orchestra composer Hector Berlioz and a slightly younger composer who might be considered Berlioz’s alter ego, Johannes Brahms.


3.7: §24. Chapter 3- Exercises
1. Underline the base of these nouns (e.g., FAM A; ORIGO, ORIGIN IS):
MILES, MILITIS; MANUS; LEX, LEGIS; LUMEN, LUMINIS; SPECIES; ONUS, ONERIS; SINUS.
2. By underlining, identify the Latin noun base within the following English words (e.g., IN FORM ALITY):
REGICIDE, DECAPITATION, EXTEMPORANEOUS, SERIAL, MORTIFY, COLLABORATE, ABOMINATION.
3. Identify each of the following Latin nouns by DECLENSION , and give its BASE and ORIGINAL LATIN MEANING:
| Latin noun | Declension | Base | Meaning |
| e.g. corpus | 3 | corpor- | body |
| a. signum | _______ | ______________ | _______________ |
| b. forma | _______ | ______________ | _______________ |
| c. radius | _______ | ______________ | _______________ |
| d. labor | _______ | ______________ | _______________ |
| e. opus | _______ | ______________ | _______________ |
| f. gradus | _______ | ______________ | _______________ |
| g. modus | _______ | ______________ | _______________ |
| h. via | _______ | ______________ | _______________ |
| i. species | _______ | ______________ | _______________ |
| j. ars | _______ | ______________ | _______________ |
4. For each of the following English words, find an English doublet—if possible, one that more closely resembles the Latin source-word:
| a. | parson | _______________ | d. | dish | _______________ |
| b. | gender | _______________ | e. | chef | _______________ |
| c. | ray | _______________ | f. | sprite | _______________ |
For Key to Exercises (Latin) , see Appendix I .


18: Equivalence relations Last updated Save as PDF Page ID 83493 Jeremy Sylvestre University of Alberta Augustana 18.1: Motivation There are often situations where we want to group certain elements of a set together as being “the same.” 18.2: Basics and Examples What properties should a relation on a set have to be useful as a notion of “equivalence”? 18.3: Classes, partitions, and quotients As desired (see Section 18.1), an equivalence relation can be used to group equivalent objects together. 18.4: Important examples Equality is the strongest form of equivalence. The “strongest” equivalence relation on a set A is the identity relation, where a≡b if and only if a=b. In this case, each equivalence class is a singleton: [a]={a} for each a∈A. 18.5: Graph for an equivalence relation Given an equivalence relation on a finite set A, what will we observe if we draw the relation's graph? 18.6: Activities 18.7: Exercises


34: Frontiers of Physics
Frontiers are exciting. There is mystery, surprise, adventure, and discovery. The satisfaction of finding the answer to a question is made keener by the fact that the answer always leads to a new question. The picture of nature becomes more complete, yet nature retains its sense of mystery and never loses its ability to awe us. The view of physics is beautiful looking both backward and forward in time. What marvelous patterns we have discovered. How clever nature seems in its rules and connections. How awesome. And we continue looking ever deeper and ever further, probing the basic structure of matter, energy, space, and time and wondering about the scope of the universe, its beginnings and future.
Thumbnail: Lattice analogy of the deformation of spacetime caused by a planetary mass. Image used wtih permission (CC-SA-BY 3.0; Mysid).


8.4: Geography of Central Asia
Unlike many other regions of the world, Central Asia lacks the distinct topographical features necessary to delineate boundaries. However, there are several broad geographical zones. The great Eurasian Steppe is a latitudinal belt of grassland that stretches from Eastern Europe through Mongolia. It was there that nomadic horse cultures flourished. Located to the south of the steppe was the core of Central Asia, an area known as Transoxiana. Beyond the Oxus River is a dry region referred to as Amu Darya today. Trade settlements and irrigated agriculture developed along the Amu Darya and Syr Darya watersheds. Finally, located to the far south, lies the mountainous area of Khorasan, the cultural capital of Persia prior to the appearance of the Mongols.


9.8: The Eighteenth Remove
We took up our packs and along we went, but a wearisome day I had of it. As we went along I saw an Englishman stripped naked, and lying dead upon the ground, but knew not who it was. Then we came to another Indian town, where we stayed all night. In this town there were four English children, captives; and one of them my own sister’s. I went to see how she did, and she was well, considering her captive condition. I would have tarried that night with her, but they that owned her would not suffer it. Then I went into another wigwam, where they were boiling corn and beans, which was a lovely sight to see, but I could not get a taste thereof. Then I went to another wigwam, where there were two of the English children; the squaw was boiling horses feet; then she cut me off a little piece, and gave one of the English children a piece also. Being very hungry I had quickly eat up mine, but the child could not bite it, it was so tough and sinewy, but lay sucking, gnawing, chewing and slabbering of it in the mouth and hand. Then I took it of the child, and eat it myself, and savory it was to my taste. Then I may say as Job 6.7, “The things that my soul refused to touch are as my sorrowful meat.” Thus the Lord made that pleasant refreshing, which another time would have been an abomination.  I told them, they had as good knock me in head as starve me to death.


7.1: Factors Affecting Public Health Policy
By the end of this section, you should be able to:
- Discuss factors affecting public health policy, including access, cost, and quality.
- Describe the influence of payment models on health care access and quality of care.
- Differentiate between the various health care delivery models.
- Define care deserts and assess their implications on health outcomes.
This section discusses factors affecting public health policy, including access, cost, and quality; payment models; care delivery models; and the impact of health care deserts on health outcomes.
Access, Cost, and Quality
In the United States, access to health care factors into many public policy discussions and decisions. Most Americans access their health care through an employer’s health insurance plan. In fact, employer-sponsored insurance in the United States covers 70 percent of workers, 36 percent of children, and 53 percent of nonworking adults (Commonwealth Fund, 2023). Although the country does not have a publicly funded universal health care system —a system that provides all people access to the full range of quality health services they need, when and where they need them, without financial hardship—the passage of the Patient Protection and Affordable Care Act (ACA) in 2010 led to millions of previously uninsured Americans receiving health care coverage (Congressional Budget Office, 2016). In addition, access to health insurance may be provided through Medicare —a government health insurance program established in 1965 that covers millions of Americans aged 65 and older and some others with disabilities , end-stage renal disease, and amyotrophic lateral sclerosis (ALS) (Medicare.gov, n.d.). Another health care access vehicle for some Americans is Medicaid , a national health insurance plan that covers some low-income families and children and individuals with disabilities. Established in 1965, Medicaid was expanded with the passage of the ACA, but because it is state-managed, its eligibility requirements and benefits differ from state to state (Centers for Medicare and Medicaid Services [CMS], 2023).
Access to health care is also impacted by technology. During the COVID-19 pandemic, telehealth , or telemedicine—delivering health care services through technology—increased dramatically (Figure 7.2). Although the use of technology to provide health care services was an essential step in providing health care at the time, its continued use poses questions about its quality and whether telehealth appointments are accessible to everyone (U.S. Government Accountability Office, 2022).
Health care cost is another factor that plays a role in public health policy discussions and decisions. The United States has one of the world’s highest costs of health care. In fact, in 2021, U.S. health care spending totaled $4.3 trillion (roughly equivalent to $12,914 per person ) (CMS, 2022). This is about twice as much as the average cost of health care per person in other developed countries.
The high spending rate per person has not led to higher health care quality in the United States. A 2021 Commonwealth Fund report ranked the United States last among 11 high-income countries on:
- access to care, with the United States ranking last on factors such health care affordability and timeliness
- health care efficiency , with the United States trailing other countries in terms of simplifying insurance, billing, and payment
- equity , with the United States ranking lowest in terms of disparities in health care experiences between lower- and higher-income groups
- health care outcomes, with the United States performing worst on outcomes such as infant mortality rate and life expectancy
How can the United States lower its health care expenditures while also increasing access to health care, health care efficiency, and equity? Policy changes are one way the United States can effect more positive outcomes. This section discusses some factors that affect health care policy, including containing costs through evolving payment models, improving client care using various client care models, and avoiding barriers to health care such as those found in health care deserts.
Payment Models
The quality of health care provided to clients in the United States depends in part on how health care professionals are allowed to administer and bill for their services. As noted earlier, despite having the highest per capita expenditure on health care across high-income countries, the United States has no universal health care system and a low quality of care. Public health policies that relate to payment models —the mechanisms by which health care services are established and paid for—may help to address this issue.
Currently, the health care system is transitioning from the traditional fee-for-service model—providers and organizations are reimbursed based upon the volume of services they provide—to payment based upon the value of those services, which includes value-based care and alternative payment models (American Hospital Association, 2023). The American Medical Association (2022) describes the most common payment models for physicians. It divides them into three categories: core payment models , supplementary payment models , and organizational models . Table 7.1 summarizes each type.
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Core Payment Models
(can exist alone without other payment types) |
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| Bundled payments ( episode-based payments ) | Physician practices receive payment based on episodes of client care according to a defined set of diagnoses and services provided to the client over a specific period. This model allows practices and health systems to achieve higher revenue by avoiding client complications, discount negotiation, and choosing a client care setting, which leads to lower costs. |
| Capitation | Physician practices receive payment to manage the client’s health condition per client per period, which is usually 1 month. The health plan applies rules that govern which clients are included within the physician practice. |
| Fee-for-service | Physician practices are paid a flat rate for each client visit, test, or procedure performed. Through this payment model, practices can achieve higher revenue with more clients and procedures each day. However, physicians may not cover their costs using this model. |
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Supplementary Payment Models
(cannot exist on their own; must coexist with one or more of the core payment models) |
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| Pay for performance | The payer pays physicians according to prescribed practice performance on defined metrics (e.g., blood pressure levels, blood glucose, hospital admissions, emergency room visits, etc.), based on the quality of care and/or utilization of care services. Providers may receive an incentive for meeting prescribed performance metric goals through pay for performance. |
| Retainer-based payment | Physician practices or other organizations receive capitation payments from the client. These payments, also known as “concierge” payments, are usually paid per client per year or month as a membership fee that covers an array of services. |
| Shared savings programs | Physicians or health care practices receive payment throughout the contract year instead of a capitation of payments during or before the year. Total costs for a specific client population are compared with a cost target which can lead to a lump-sum payment incentive or penalty for not meeting prescribed goals. |
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Organizational Models
(combined payment models that create additional payment models) |
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| Accountable care organizations (ACOs) | Large health systems where an individual physician practice or a collection of physicians enter into a contract with a payer, typically under a fee-for-service payment model, to provide care to a population of clients. This network is responsible for improving health outcomes and reducing spending for a particular client population. Organizations may include physician groups, health systems, hospitals, and behavioral health organizations. |
| Medical homes | An integrated team of health care providers such as nurses, physicians, and care managers provides care that addresses the “whole person.” Organizations can become recognized as accredited “Patient-Centered Medical Homes” through the National Committee for Quality Assurance (NCQA). The main source of revenue for most practices is fee-for-service payments; they may also receive additional payments in enhanced fee-for-service payment rates, per-month patient care management fees, and pay-for-performance payments for high performance on measures of quality, client experience, or cost. |
Like physicians, health care organizations are reimbursed in different ways, including prospective payment systems , bundled payments, and Accountable Care Organizations (American Hospital Association [AHA], 2023). Recently, value-based purchasing programs have significantly changed hospitals’ approach to providing care. For example, the Hospital Value-Based Purchasing Program bases Medicare payments on the quality of care rather than the services performed. Hospitals with higher rates of post-operative infections, ventilator-associated pneumonia, and other negative outcomes associated with hospital care receive decreased reimbursement. Accordingly, hospitals are incentivized to focus on health care quality. Another example of a reimbursement structure designed to increase the providers’ quality of care is the Hospital Readmissions Reduction Program . This program, administered through the CMS, penalizes hospitals with higher-than-expected levels of readmissions.
This complex framework of health care reimbursement influences how and where care is provided to clients and by whom (National Academies of Sciences, Engineering, and Medicine [NASEM] et al., 2021a). Accordingly, payment systems can affect nurses’ ability to address a community’s health needs. For example, the traditional fee-for-service payment system that focuses on physician reimbursement does not recognize the value of care provided by other health care team members, including nurses (NASEM et al., 2021a). This limits the ability of the health care system to address the social determinants of health (SDOH). It is currently unclear which newer payment model(s) will prevail and become dominant. However, nurses have the opportunity to make a more measurable impact in the newer reimbursement models. For example, nurses working as case managers and care coordinators can help manage a population’s health and reduce costs associated with chronic illness (NASEM et al., 2021a). Overall, community nurses will be better able to promote continuity of care between the health systems and clients at home.
Care Delivery Models
The payment models previously described are the foundation for delivering care. Care delivery models refer to how health care providers work together to provide health care to clients. One example of a care delivery model is the collaborative care model , which “seeks to impact the clinical outcomes of patients who present with depression in primary care” (Collaborative Family Healthcare Association, 2023). Through this model, a psychiatrist and care manager are members of an interdisciplinary care team that manages a group of clients who have been screened for depression and need a higher level of intervention to achieve positive health outcomes. In addition to addressing the clients’ behavioral and psychological needs, the team addresses physical needs, such as the maintenance of chronic diseases (e.g., diabetes, hypertension, cancer, and heart disease). Through this model, health care team members collaborate to achieve the common goal of ensuring the best possible health outcomes for clients.
According to the AHA (2019a), to achieve better outcomes for clients, hospitals and health systems across the United States have had to redesign how they provide client care. The AHA identifies four care models as the most common in the United States: accountable care organizations and medical homes, previously defined in Table 7.2, integrated service lines, and provider-sponsored health plans.
With integrated service lines , hospitals and health care systems organize around specific disease states such as cancer, heart disease, and diabetes throughout the continuum of client care. This model contrasts the traditional care provision, where service lines based on disease state are siloed. In provider-sponsored health plans , plans are either sponsored or acquired by hospitals, physician groups, or health systems, which take over responsibility for the total cost of care for the clients enrolled in the health plan. These organizations may often take on financial risks of providing care for the clients enrolled in the health plan.
Table 7.2 provides examples of these four care delivery models. The type of care model health care professionals choose to provide care is in part determined by health care policy and, in part, determines health care policies based on the revenues and outcomes it achieves.
| Care Delivery Model | Example and Key Results |
|---|---|
| Accountable care organizations | Caravan Health partners with rural and independent health systems to ensure positive client outcomes. This has led to 60 percent or higher cost savings and improved quality scores. |
| Integrated service lines | New York’s Mount Sinai Health System utilizes a care guide that visits clients in the hospital and coordinates client care transition to home, post-hospital follow-up, and transportation as needed for appointments. This has resulted in emergency room utilization dropping from 26 percent to 3 percent. |
| Medical homes | Ohio’s Summa Health provides care to clients through an integrated, team-based approach where primary care is the focus. Every aspect of the client’s health, including physical and social issues, is addressed. This has led to lower hospital readmission rates. Today, 77 percent of Summa Health’s primary care practices are accredited as Patient-Centered Medical Homes. |
| Provider-sponsored health plans | Sharp HealthCare in San Diego County, California, offers a care management program across the entire client care continuum. The Sharp health plan is the highest-rated organization of its kind in the state of California. |
Care Deserts
Care deserts (or medical deserts ) are areas where individuals have limited access to health care services such as hospitals or health clinics (Nguyen & Kim, 2021). Care deserts are most often found in rural areas and in tribal communities and can take many forms, including limited to no access to maternal health services— maternal care deserts —or limited to no access to pharmacy services— pharmacy deserts . More than 80 percent of counties in the United States lack proper access to needed medical services (Nguyen & Kim, 2021). Almost 50 million Americans are more than 60 minutes from a level I and II trauma center (Soto et al., 2018). It is estimated that over one-third of the U.S. population lives in counties that lack sufficient health care infrastructure to ensure good health outcomes. This may include a lack of access to services, medications, primary care providers, hospitals, and community health centers (Nguyen & Kim, 2021). For example, 136 rural hospitals closed between 2010 and 2021; 19 went out of business in 2020, the highest number since 2005 (AHA, 2022). Although this number dropped dramatically in 2021—when only two rural hospitals closed—the improvement may be attributed to federal relief funds associated with the COVID-19 pandemic that have now ended (Levinson et al., 2023). While fewer urban hospitals have closed over the past decade, those that do close tend to be in lower-income communities and treat clients who are uninsured or covered by Medicaid (KFF, 2020b). Closures of hospitals have compound effects because they are sometimes the only form of care to which local residents have access (Figure 7.3) (AHA, 2019b).
A care desert may be created for various reasons. One contributing factor is demographic shifts . Over the past decades, many rural areas in the United States have experienced a sharp decrease in their overall population. Such shifts lead to declines in revenue for health care providers like hospitals and health clinics. Because of this, organizations may choose to leave less populated areas for more populated ones. Health care providers also have little motivation to offer care in neighborhoods where many people are uninsured or underinsured or covered through Medicare and Medicaid. Medicaid reimburses health care providers at a lower rate than private insurance companies such as Blue Cross Blue Shield (KFF, 2020a). As such, there is often a hesitancy to offer care in areas with a high rate of Medicaid-eligible individuals.
This news video from Illinois reports on how health care professionals and physicians working in underserved communities face an uncertain future related to challenges receiving Medicaid reimbursement.
Watch the video, and then respond to the following questions.
- How many clients rely on Medicaid, according to the video?
- How many Medicaid claims are denied as compared with claims from private insurance?
- Why are doctors who accept clients who use Medicaid losing money?
- How are difficulties with Medicaid contributing to medical deserts?
Communities that lack high-quality schools or work opportunities for spouses of medical professionals may find it difficult to recruit health care providers such as primary care and specialty care providers (Association of American Medical Colleges, 2023; Health Resources and Services Administration [HRSA], 2023). Research shows that although 20 percent of the U.S. population lives in rural areas, fewer than 10 percent of U.S. doctors practice in rural communities (Joynt et al., 2016). This exacerbates care deserts.
Lack of access to health care in such care deserts leads to many negative health outcomes, including untreated health problems and chronic diseases such as diabetes and hypertension. Communities with less access to primary care struggle with disease diagnosis and prevention, client education , and treating acute and chronic illnesses. Lack of health care access especially affects communities of color (Alfred, 2022).
Finally, clients who must travel long distances to secure care lose valuable work time and incur costs related to travel. In contrast to urban areas, rural regions frequently lack public transportation services. Older adult clients often have chronic conditions, the management of which may necessitate frequent medical appointments (Rural Health Information Hub [RHIhub], 2022). When rural hospitals close, employment opportunities in the community decrease, as the hospital may be one of the main employers in that community, and local economies suffer through revenue loss and tax base loss (AHA, 2019b; Harsha, 2022).
As discussed in Demographic Trends and Societal Changes, care deserts are often addressed using technology such as telemedicine . Because the health care provider (e.g., physician, nurse practitioner, or other specialist) can provide care to individuals remotely, clients in care deserts can receive routine health care (RHIhub, 2021). However, in many areas, clients are still left without access to emergency, inpatient, and surgical care. Many also lack access to simple urgent care for conditions like acute pharyngitis because group A Streptococcus (group A strep) tests must currently be done in person, not via telehealth. Finally, in-person primary care visits for screenings like skin cancer are still preferred to telehealth until the technology improves.
The government offers some care options to those living in care deserts through Federally Qualified Health Centers (FQHCs). These federally funded nonprofit health centers or clinics serve “medically underserved” areas and populations throughout the United States. FQHCs provide primary care services to all individuals, even those not able to pay, on a sliding scale basis (HealthCare.gov, n.d.).
This video provides an overview of FQHCs, also known as community health centers.
Watch the video, and then respond to the following questions.
- What types of care do FQHCs provide to the communities they serve?
- Who is eligible to seek care at an FQHC?
One organization seeking to address physician shortages in health care deserts is the National Health Services Corps , which is operated by the Health Resources and Services Administration (HRSA) arm of the U.S. Department of Health and Human Services (HHS). This organization connects underserved rural, urban, and tribal communities with health care providers. The organization’s 20,000 members currently provide care to over 21 million people in the United States in over 9,000 community health care sites (HRSA, 2023). The organization offers loan repayment and scholarships to its member health care practitioners, making practicing in underserved areas more appealing.
In its report Nowhere to Go: Maternity Care Deserts Across the U.S. 2022 Report , the March of Dimes recommends several policy solutions to federal and state governments to reduce maternity care deserts (March of Dimes, 2022). Recommended solutions include passing a Medicaid postpartum extension from 60 days to 12 months, expanding telehealth services to bridge gaps in health care, and strengthening network requirements for health care plans made available through the ACA (March of Dimes, 2022).
According to the National Academies of Sciences, Engineering, and Medicine (NASEM, 2021b), nurses play a significant role in addressing health inequities such as the lack of qualified health care professionals and the lack of access to health services available to populations. The NASEM (2021b) points to the profession’s deep roots in community health advocacy and social justice , which refers to seeking to ensure equal access to health care services for everyone within a society. The NASEM identifies five key roles to improve health equity for populations: awareness, adjustment, assistance, alignment, and advocacy (NASEM, 2021b). Let’s briefly discuss each.
- With awareness, the nurse seeks to identify and understand social risks and opportunities for a select population. For example, the nurse would inquire about the availability of quality housing and health care services for the population.
- Adjustment has to do with incorporating activities that seek to accommodate populations to address identified barriers, such as providing care through telehealth for individuals lacking adequate transportation .
- Assistance refers to actions the nurse takes to connect populations with various resources such as providing transportation vouchers to ensure individuals have a means by which to get to and from appointments.
- Alignment refers to the actions of the nurse or a health care system to understand the needs of a community or population and implement mechanisms to address health inequities such as investing in ridesharing or time-bank programs, which are geared at increasing access to health care services.
- Advocacy has to do with partnerships between organizations to promote policies that create and deploy programming to address health inequities within communities, such as improving infrastructure that improves transportation for individuals with limited transportation to and from health care services.
Since its inception, the nursing profession has been heavily involved in ensuring everyone has equal access to resources. As such, the community health nurse and the advanced practice nurse are key partners in minimizing health inequities within communities (NASEM, 2021b).