3.1: Mesopotamia
The Mesopotamian Cultures
Sumer was an ancient Chalcolithic civilization that saw its artistic styles change throughout different periods in its history.
Discuss the historical importance of the various civilizations that existed in Mesopotamia
Key Points
- The Eridu economy produced abundant food, which allowed its inhabitants to settle in one location and form a labor force specializing in diverse arts and crafts.
- Writing produced during the early Sumerian period suggest the abundance of pottery and other artistic traditions.
- Elements of the early Sumerian culture spread through a large area of the Near and Middle East.
- The Sumerian city states rose to power during the prehistorical Ubaid and Uruk periods.
Key Terms
- theocratic :A form of government in which a deity is officially recognized as the civil ruler. Official policy is governed by officials regarded as divinely guided, or is pursuant to the doctrine of a particular religion or religious group.
- casting :A sculptural process in which molten material (usually metal) is poured into a mold, allowed to cool and harden, and become a solid object.
- Cuneiform :One of the earliest known forms of written expression that began as a system of pictographs. It emerged in Sumer around the 30th century BC, with predecessors reaching into the late 4th millennium (the Uruk IV period).
- Chalcolithic :Also known as the Copper Age, a phase of the Bronze Age in which the addition of tin to copper to form bronze during smelting remained yet unknown. The Copper Age was originally defined as a transition between the Neolithic and the Bronze Age.
Sumer was an ancient civilization in southern Mesopotamia (modern Iraq) during the Chalcolithic and Early Bronze Ages. Although the historical records in the region do not go back much further than ca. 2900 BCE, modern historians believe that Sumer was first settled between ca. 4500 and 4000 BCE by people who may or may not have spoken the Sumerian language. These people, now called the “Ubaidians,” were the first to drain the marshes for agriculture; develop trade; and establish industries including weaving, leatherwork, metalwork , masonry, and pottery.
The Sumerian city of Eridu, which at that time bordered the Persian Gulf, is believed to be the world’s first city. Here, three separate cultures fused—the peasant Ubaidian farmers, the nomadic Semitic-speaking pastoralists (farmers who raise livestock), and fisher folk. The surplus of storable food created by this economy allowed the region’s population to settle in one place, instead of migrating as hunter-gatherers. It also allowed for a much greater population density, which required an extensive labor force and a division of labor with many specialized arts and crafts.
An early form of wedge-shaped writing called cuneiform developed in the early Sumerian period. During this time, cuneiform and pictograms suggest the abundance of pottery and other artistic traditions. In addition to the production of vessels , clay was also used to make tablets for inscribing written documents. Metal also served various purposes during the early Sumerian period. Smiths used a form of casting to create the blades for daggers. On the other hand, softer metals like copper and gold could be hammered into the forms of plates, necklaces, and collars.
By the late fourth millennium BCE, Sumer was divided into about a dozen independent city-states delineated by canals and other boundary makers. At each city center stood a temple dedicated to the particular patron god or goddess of the city. Priestly governors ruled over these temples and were intimately tied to the city’s religious rites.
The Ubaid Period
The Ubaid period is marked by a distinctive style of painted pottery, as seen in the example below, produced domestically on a slow wheel. This style eventually spread throughout the region. During this time, the first settlement in southern Mesopotamia was established at Eridu by farmers who first pioneered irrigation agriculture. Eridu remained an important religious center even after nearby Ur surpassed it in size.
The Uruk Period
The transition from the Ubaid period to the Uruk period is marked by a gradual shift to a great variety of unpainted pottery mass-produced by specialists on fast wheels. The trough below is an example of pottery from this period.
By the time of the Uruk period (ca. 4100–2900 BCE), the volume of trade goods transported along the canals and rivers of southern Mesopotamia facilitated the rise of many large, stratified , temple-centered cities where centralized administrations employed specialized workers. Artifacts of the Uruk civilization have been found over a wide area—from the Taurus Mountains in Turkey, to the Mediterranean Sea in the west, and as far east as Central Iran. The Uruk civilization, exported by Sumerian traders and colonists, had an effect on all surrounding peoples, who gradually developed their own comparable, competing economies and cultures.
Sumerian cities during the Uruk period were probably theocratic and likely headed by priest-kings ( ensis ), assisted by a council of elders, including both men and women. The later Sumerian pantheon (gods and goddesses) was likely modeled upon this political structure. There is little evidence of institutionalized violence or professional soldiers during the Uruk period. Towns generally lacked fortified walls, suggesting little, if any, need for defense. During this period, Uruk became the most urbanized city in the world, surpassing for the first time 50,000 inhabitants.
Gilgamesh
The earliest king authenticated through archaeological evidence is Enmebaragesi of Kish, whose name is also mentioned in the Gilgamesh epic (ca. 2100 BCE)—leading to the suggestion that Gilgamesh himself might have been a historical king of Uruk. As the Epic of Gilgamesh shows, the second millennium BCE was associated with increased violence. Cities became walled and increased in size as undefended villages in southern Mesopotamia disappeared.
Ceramics in Mesopotamia
The invention of the potter’s wheel in the fourth millennium BCE led to several stylistic shifts and varieties in form of Mesopotamian ceramics.
Differentiate Ubaid pottery from later styles in Mesopotamian ceramics
Key Points
- The invention and evolution of the potter’s wheel allowed individuals to produce vessels at increasing speeds and in increasing numbers.
- Ubaid pottery was more decorative and unique than Uruk pottery.
- As ceramics evolved, shapes and sizes of clay objects became more varied.
- Clay could also be used for writing tablets that could be fired, if the owner believed the text was important.
Key Terms
- ceramics :The craft of making objects from clay.
- throwing :Shaping clay on a potter’s wheel.
- stylus :A writing implement that incises lines into surfaces, such as clay.
- kiln :A special kind of oven used for firing ceramic objects at high temperatures.
Although ceramics developed in East Asia c. 20,000-10,000 BCE, the practice of throwing arose with the invention of the potter’s wheel in Mesopotamia around the fourth millennium BCE. The earliest clay vessels date to the Chalcolithic Era, which is divided into the Ubaid (5000-4000 BCE) and Uruk (4000-3100 BCE) periods.
The Chalcolithic Era
The Ubaid period is marked by a distinctive style of fine quality painted pottery which spread throughout Mesopotamia. Ceramists produced vases, bowls, and small jars domestically on slow wheels, painting unique abstract designs on the fired clay.
Experts differentiate the Ubaid period from the Uruk period by the style of pottery produced in each era. During the Uruk period, the potter’s wheel advanced to allow for faster speeds. As such, ceramists could produce pottery more quickly, leading to the mass production of standardized, unpainted styles of vessels.
The Akkiadian Empire
As the Akkadian Empire overtook the Sumerian city-states , ceramists continued to produce bowls, vases, jars, and other objects in a variety of shapes and sizes. Like Uruk pottery, the surfaces of these objects were left unpainted, although some vessels appear to have a form of abstract reliefs on the surface. This photograph displays the various forms (including a form that resembles a present-day cake stand) that pottery took during the Akkadian Empire.
Ur III
The Third Ur Dynasty , better known as Ur III, witnessed the continuation of unpainted ceramic vessels that took a variety of forms. This photograph depicts an urn that resembles today’s flower vases, as well as bowls, cups, and a smaller vase.
As in previous eras, clay was also used to produce writing tablets that were incised with styluses fashioned from blunted reeds. Often, tablets were used for record-keeping (the ancient version of an office memo). Like other ceramic objects, tablets could be fired in a kiln to produce a permanent form if the text was believed significant enough to preserve. The tablets in the photograph below contain information about farm animals and workers.
Babylonian Ceramics
Pottery produced during the “Old” Babylonian period shows a return to painted abstract designs and increased variety in forms. In this photograph, a bowl, a jar, and a goblet show remnants of paint on their exteriors.
Sculpture in Mesopotamia
While the purposes that Mesopotamian sculpture served remained relatively unchanged for 2000 years, the methods of conveying those purposes varied greatly over time.
Identify the purposes of the sculptures featured in this concept
Key Points
- Mesopotamian sculptures were predominantly created for religious and political purposes.
- Common materials included clay, metal, and stone fashioned into reliefs and sculptures in the round .
- The Uruk period marked a development of rich narrative imagery and increasing lifelikeness of human figures.
- Hieratic scale was often used in Mesopotamian sculpture to convey the significance of gods and royalty.
- After the end of the Uruk period, subject matter began to depict scenes of warfare and became increasingly violent and intimidating.
Key Terms
- register :A usually horizontal division of separate scenes in two- or three-dimensional art.
- hieratic scale :A visual method of marking the significance of a figure through its size. The more important a figure is, the larger it appears.
- terra cotta :Clay that has been fired in a kiln.
- high relief :A sculpture that projects significantly from its background, providing deep shadows.
- votive :An object left in temples or other religious locations for a variety of spiritual purposes.
- colossal :Extremely tall.
- lyre :A hand-held stringed instrument resembling a small harp.
- cylinder seal :A small object adorned with carved images of animals, writing, or both, used to sign official documents.
- in the round :Sculpture that stands freely, separate from a background.
- relief :A sculpture that projects from a background.
- mixed-media :Artwork consisting of two or more different materials.
- nomadic :Mobile; moving from one place to another, never settling in one location for too long.
The current archaeological record dates sculpture in Mesopotamia the tenth millennium BCE, before the dawn of civilization . Sculptural forms include humans, animals, and cylinder seals with cuneiform writing and imagery in the round or as reliefs. Materials range from terra cotta , stones like alabaster and gypsum, and metals like copper and bronze .
Hunter-Gatherers and Samarra
Because the artists of the hunter-gatherer era were nomadic , the sculptures they produced were small and lightweight. Even after cultures discovered agricultural methods, such as irrigation and animal domestication, artists continued to produce small sculptures. The seated female figure below (c. 6000 BCE), likely carved from a single stone, hails from the prehistoric Samarra culture (5500-4800 BCE). Like many prehistoric female figures, the features of this sculpture suggest that it was used in fertility rituals . Its breasts are accentuated, and its legs are spread in a position that might resemble a woman in labor. While the artist emphasized areas of the body related to reproduction, he or she did not add facial features or feet to the figure.
Uruk Period
Spirituality and communication are reflected in sculptures dating the Uruk period (4000-3100 BCE) of the late prehistoric era. Scholars believe that the gypsum Uruk trough was used as part of an offering to Inanna, the goddess of fertility, love, war, and wisdom. In addition to reliefs of animals, reliefs of reed bundles, sacred objects associated with Inanna, adorn the exterior of the trough. For these reasons, scholars do not believe the trough was used for agricultural purposes.
Animals, along with forms of writing, also appear on early cylinder seals, which were carved from stones and used to notarize documents. Officials or their scribes rolled the seals on wet clay tablets as a form of signature. Cylinder seals were also worn as jewelry and have been found along with precious metals and stones in the tombs of the elite members of society. The trough, cylinder seals, and various other sculptures of the Uruk period serve as examples of the rich narrative imagery that arose during this time.
The Uruk period also marked an evolution in the depiction of the human body, as seen in the Mask of Warka (c. 3000 BCE), named for the present-day Iraqi city in which it was discovered. This marble “mask” is all that remains of a mixed- media sculpture that also consisted of a wooden body, gold leaf “hair,” inlaid “eyes” and “eyebrows,” and jewelry. Like most sculptures produced during the time, the sculpture was originally painted in an attempt to make it look lifelike.
Early Dynastic Period
Sculpture built on older traditions and grew more complex during the Early Dynastic Period (2900-2350 BCE). Although artists still used clay and stone, copper became the dominant medium. Subject matter focused on spiritual matters, war, and social scenes.
A cylinder seal discovered in the royal tomb of Queen Puabi depicts two registers of a palace banquet scene punctuated by cuneiform script, marking a growing complexity in the imagery of this form of notarization. Each register features hieratic scale, in which the queen (upper register) and the king (lower register) are larger than their subjects.
Another sculpture of note is a mixed-media bull’s head that once adorned a ceremonial lyre found in Puabi’s tomb in Ur. The head consists of a gold “face,” lapis lazuli (a blue precious stone) “fur,” and shell “horns.” Although much of the lyre, whose dominant material was wood, disintegrated over time, contemporaneous imagery depicts lyres with similar decoration. Scholars believe that lyres were used in burial ceremonies and that the music that was played held religious significance.
Sculptures in human form were also used as votive offerings in temples. Among the best known are the Tell Asmar Hoard, a group of 12 sculptures in the round depicting worshipers, priests, and gods. Like the cylinder seal found in Queen Puabi’s tomb, the figures in the Tell Asmar Hoard show hieratic scale. Worshipers, as in the image below, stand with their arms in front of their chests and their hands in the position of holding offerings. Materials range from alabaster to limestone to gypsum, depending on each figure’s significance. One common feature is the large hollowed out eye sockets, which were once inlaid with stone to make them appear lifelike. The eyes held spiritual significance, especially that of the gods, which represented awesome otherworldly power.
Akkadian Empire
During the period of the Akkadian Empire (2271-2154 BCE), sculpture of the human form grew increasingly naturalistic, and its subject matter increasingly about politics and warfare.
 Although the stylized features dominate the sculpture, the level of naturalism was unprecedented.
The Victory Stele of Naram Sin provides an example of the increasingly violent subject matter in Akkadian art, a result of the violent and oppressive climate of the empire. Here, the king is depicted as a divine figure, as signified by his horned helmet. In typical hieratic fashion, Naram Sin appears larger than his soldiers and his enemies. The king stands among dead or dying enemy soldiers as his own troops look on from a lower vantage point. The figures are depicted in high relief to amplify the dramatic significance of the scene. On the right hand side of the stele, cuneiform script provides narration.
Babylon and Assyria
The second millennium BCE marks the transition from the Middle Bronze Age to the Late Bronze Age . The most prominent cultures in the ancient Near East during this period were Babylonia and Assyria. Clay was the dominant medium during this time, but stone was also used. The most common surviving forms of second millennium BCE Mesopotamian art are cylinder seals, relatively small free-standing figures, and reliefs of various sizes. These included cheap plaques, both religious and otherwise, of molded pottery for private homes.
Babylonian culture somewhat preferred sculpture in the round to reliefs. Depictions of human figures were naturalistic. The Assyrians, on the other hand, developed a style of large and exquisitely detailed narrative reliefs in painted stone or alabaster. Intended for palaces, these reliefs depict royal activities such as battles or hunting. Predominance is given to animal forms, particularly horses and lions, which are represented in great detail. Human figures are static and rigid by comparison, but also minutely detailed. The Assyrians produced very little sculpture in the round with the exception of colossal guardian figures, usually lions and winged beasts, that flanked fortified royal gateways. While Assyrian artists were greatly influenced by the Babylonian style, a distinctly Assyrian artistic style began to emerge in Mesopotamia around 1500 BCE.
Architecture in Mesopotamia
Domestic and public architecture in Mesopotamian cultures differed in relative simplicity and complexity. As time passed, public architecture grew to monumental heights.
Differentiate how Mesopotamian cultures approached domestic and public architecture
Key Points
- Mesopotamian cultures used a variety of building materials. While mud brick is the most common, stone also features as a structural and decorate element.
- The ziggurat marked a major architectural accomplishment for the Sumerians , as well as subsequent Mesopotamian cultures.
- Palaces and other public structures were often decorated with glaze or paint, stones, or reliefs .
- Animals and human-animal hybrids feature in the religions of Mesopotamian cultures and were often used as architectural decoration.
Key Terms
- alto relief :A sculpture with significant projection from its background.
- bas reliefs :Sculptures that minimally project from their backgrounds.
- public sphere :The world outside the home.
- ziggurat :A towering temple, similar to a stepped pyramid, that sat in the center of Mesopotamian city-states in honor to the local pantheon.
- private sphere :The home, or the domestic realm.
- load-bearing :A form of architecture in which the walls are the structure’s main source of support.
- stacking and piling :A form of load-bearing architecture in which the walls are thickest at the base and grow gradually thinner toward the top.
-
pilaster
:
A rectangular column that projects partially from the wall to which it is attached; it gives the appearance of a support, but is only for decoration.
The Mesopotamians regarded “the craft of building” as a divine gift taught to men by the gods, and architecture flourished in the region. A paucity of stone in the region made sun baked bricks and clay the building material of choice. Babylonian architecture featured pilasters and columns , as well as frescoes and enameled tiles. Assyrian architects were strongly influenced by the Babylonian style , but used stone as well as brick in their palaces, which were lined with sculptured and colored slabs of stone instead of being painted. Existing ruins point to load-bearing architecture as the dominant form of building. However, the invention of the round arch in the general area of Mesopotamia influenced the construction of structures like the Ishtar Gate in the sixth century BCE.
Domestic Architecture
Mesopotamian families were responsible for the construction of their own houses. While mud bricks and wooden doors comprised the dominant building materials, reeds were also used in construction. Because houses were load-bearing, doorways were often the only openings. Sumerian culture observed a rigid division between the public sphere and the private sphere , a norm that resulted in a lack of direct view from the street into the home. The sizes of individual houses varied, but the general design consisted of smaller rooms organized around a large central room. To provide a natural cooling effect, courtyards became a common feature in the Ubaid period and persist into the domestic architecture of present-day Iraq.
Ziggurats
One of the most remarkable achievements of Mesopotamian architecture was the development of the ziggurat, a massive structure taking the form of a terraced step pyramid of successively receding stories or levels, with a shrine or temple at the summit. Like pyramids, ziggurats were built by stacking and piling . Ziggurats were not places of worship for the general public. Rather, only priests or other authorized religious officials were allowed inside to tend to cult statues and make offerings . The first surviving ziggurats date to the Sumerian culture in the fourth millennium BCE, but they continued to be a popular architectural form in the late third and early second millennium BCE as well .
The image below is an artist’s reconstruction of how ziggurats might have looked in their heyday. Human figures appear to illustrate the massive scale of these structures. This impressive height and width would not have been possible without the use of ramps and pulleys.
Political Architecture
The exteriors of public structures like temples and palaces featured decorative elements such as bright paint, gold, leaf, and enameling. Some elements, such as colored stones and terra cotta panels, served a twofold purpose of decoration and structural support, which strengthened the buildings and delayed their deterioration.
Between the thirteenth and tenth centuries BCE, the Assyrians replaced sun-baked bricks with more durable stone and masonry. Colored stone and bas reliefs replaced paint as decoration. Art produced under the reigns of Ashurnasirpal II (883-859 BCE), Sargon II (722-705 BCE), and Ashurbanipal (668-627 BCE) inform us that reliefs evolved from simple and vibrant to naturalistic and restrained over this time span.
From the Early Dynastic Period (2900-2350 BCE) to the Assyrian Empire (25th century-612 BCE), palaces grew in size and complexity. However, even early palaces were very large and ornately decorated to distinguish themselves from domestic architecture. Because palaces housed the royal family and everyone who attended to them, palaces were often arranged like small cities, with temples and sanctuaries , as well as locations to inter the dead. As with private homes, courtyards were important features of palaces for both utilitarian and ceremonial purposes.
By the time of the Assyrian empire, palaces were decorated with narrative reliefs on the walls and outfitted with their own gates. The gates of the Palace of Dur-Sharrukin, occupied by Sargon II, featured monumental alto reliefs of a mythological guardian figure called a lamassu (also known as a shedu ), which had the head of a human, the body of a bull or lion, and enormous wings. Lamassu figure in the visual art and literature from most of the ancient Mesopotamian world, going as far back as ancient Sumer (settled c. 5500 BCE) and standing guard at the palace of Persepolis (550-330 BCE).
Although the Romans often receive credit for the round arch, this structural system actually originated during ancient Mesopotamian times. Where typical load-bearing walls are not strong enough to have many windows or doorways, round arches absorb more pressure, allowing for larger openings and improved airflow. The reconstruction of Dur-Sharrukin shows that the round arch was being used as entryways by the eighth century BCE.
Perhaps the best known surviving example of a round arch is in the Ishtar Gate, which was part of the Processional Way in the city of Babylon. The gate, now in the Pergamon Museum in Berlin, was lavishly decorated with lapis lazuli complemented by blue glazed brick. Elsewhere on the gate and its connecting walls were painted floral motifs and bas reliefs of animals that were sacred to Ishtar, the goddess of fertility and war.
The photograph above shows the immense scale of the gate. The photograph below shows the detail of a relief of a bull from the gate’s wall.
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- Lyres of Ur. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Lyres_of_Ur. License : CC BY-SA: Attribution-ShareAlike
- Burney Relief. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Burney_Relief. License : CC BY-SA: Attribution-ShareAlike
- Choghazanbil2.jpg. Provided by : Wikimedia Commons. Located at : en.Wikipedia.org/wiki/Chogha_Zanbil#/media/File:Choghazanbil2.jpg. License : CC BY-SA: Attribution-ShareAlike
- 542px-Lammasu.jpg. Provided by : Wikimedia Commons. Located at : en.Wikipedia.org/wiki/Lamassu#/media/File:Lammasu.jpg. License : CC BY-SA: Attribution-ShareAlike
- 568px-Palace_of_Khorsabad.png. Provided by : Wikimedia Commons. Located at : en.Wikipedia.org/wiki/File:Palace_of_Khorsabad.png. License : Public Domain: No Known Copyright
- 320px-Ish-tar_Gate_detail.jpg. Provided by : Wikimedia Commons. Located at : en.Wikipedia.org/wiki/Ishtar_Gate#/media/File:Ish-tar_Gate_detail.jpg. License : CC BY-SA: Attribution-ShareAlike
- 32487-ziggurat-mesopotamia.jpg. Provided by : Wikispaces. Located at : mesopotamiadiv1.wikispaces.com/Architecture. License : CC BY-SA: Attribution-ShareAlike
- Ishtar Gate. Provided by : Wikimedia Commons. Located at : en.Wikipedia.org/wiki/File:Ishtar_Gate_at_Berlin_Museum.jpg#/media/File:Ishtar_Gate_at_Berlin_Museum.jpg. License : CC BY: Attribution
- Ishtar Gate. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Ishtar_Gate. License : CC BY-SA: Attribution-ShareAlike
- Sargon II. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Sargon_II. License : CC BY-SA: Attribution-ShareAlike
- Lamassu. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Lamassu. License : CC BY-SA: Attribution-ShareAlike
- Mesopotamia. Provided by : Wikispaces. Located at : mesopotamiadiv1.wikispaces.com/Architecture. License : CC BY-SA: Attribution-ShareAlike
- Ashurbanipal. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Ashurbanipal. License : CC BY-SA: Attribution-ShareAlike
- Ashurnasirpal II. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Ashurnasirpal_II. License : CC BY-SA: Attribution-ShareAlike
- Architecture of Mesopotamia. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Architecture_of_Mesopotamia. License : CC BY-SA: Attribution-ShareAlike
- Assyria. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Assyria. License : CC BY-SA: Attribution-ShareAlike
- Early Dynastic Period (Mesopotamia). Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Early_Dynastic_Period_(Mesopotamia). License : CC BY-SA: Attribution-ShareAlike
- Sumer. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Sumer. License : CC BY-SA: Attribution-ShareAlike
- Persepolis. Provided by : Wikipedia. Located at : en.Wikipedia.org/wiki/Persepolis. License : CC BY-SA: Attribution-ShareAlike


8.7: A Brief History of Prisons and Jails
The Growth of Jails in the United States
jail (GOAL – old English spelling) is yet another concept that we have carried with us from Western Europe (England, etc…) when the United States was first forming. Spawning from the County-level establishment and management of jails in England, these have largely been run by County Sheriffs in the United States, ever since we began to have them. They have had various names, depending on their function and use, such as Bridewells , and Workhouses. Pictured below is what is commonly accepted as the first “built” structure to house individuals that have been processed through the courts, the Walnut Street Jail. Opening around 1790, this facility housed both jail inmates, and at some points in time convicted offenders.
Table 2-1 Jails in the United States
This is due to a variety of reasons, to include: inclusion or exclusion of Youth Facilities, Native American Facilities, Privately Owned Facilities, and reporting structures (who reports a jail in a given year). Based on these fluctuations, it is difficult to get an exact count of jails each year. However, it appears that there are roughly 3,300 jails in the United States today.
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Cahalan, M. W., & Parsons, L. A. (1986). Historical corrections statistics in the United States, 1850-1984.
U.S. Department of Justice.
https://www.bjs.gov/content/pub/pdf/hcsus5084.pdf
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Harrison, P. M., & Beck, A. J. (2005). Prisons and jail inmates at midyear,
2005.BJS Bulletin
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https://www.bjs.gov/content/pub/pdf/pjim05.pdf
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4.14: Avoiding Plagiarism
Identify instances of plagiarism, both intentional and unintentional
As discussed in the previous page, incidents of plagiarism and related ethical violations are unfortunately common features of contemporary life, both in and out of our work environments. The video below from 2016 describes 10 famous cases:
Both intentional and unintentional plagiarism are problems, and you should do everything you can to keep them from happening. It is obvious that intentional plagiarism would be a gross violation; however, unintentional plagiarism is a bit more difficult to nail down.
As the UNSW Sydney’s page for their current students describes, “most incidents of plagiarism are the product not of deliberate cheating, but of underdeveloped academic skills.” [1] Often the problem isn’t with the ethical standing of the author but with something else, such as lack of time, lack of clear notes, and lack of understanding of proper referencing. Thus, the basic rule of thumb for avoiding plagiarism is three-fold:
- If you even suspect the idea is someone else’s, take the time to go back through notes, Google, or other reputable sources, and search for the author.

- If you are not sure of authorship, consider using other evidence or sources to articulate your idea.
There are, however, a very few things that don’t require attributions: scientific or mathematical equations and “common knowledge.” You don’t have to provide a citation if you include the equation E = mc 2 , but you do need to attribute a quote that explains the history of the equation’s discovery. You don’t have to provide a citation if you include the fact that gravity exists, but you do need to provide a citation for a study that discusses how gravity impacts astronauts on the ISS.
- UNSW Sydney. " How Does Plagiarism Happen? " Web. 18 June 2018.


21.4: The Adaptive Immune Response - B Lymphocytes and Antibodies
Learning Objectives
- Explain how B cells mature and how B cell tolerance develops
- Discuss how B cells are activated and differentiate into plasma cells
- Describe the structure of the antibody classes and their functions
Antibodies were the first component of the adaptive immune response to be characterized by scientists working on the immune system. It was already known that individuals who survived a bacterial infection were immune to re-infection with the same pathogen. Early microbiologists took serum from an immune patient and mixed it with a fresh culture of the same type of bacteria, then observed the bacteria under a microscope. The bacteria became clumped in a process called agglutination. When a different bacterial species was used, the agglutination did not happen. Thus, there was something in the serum of immune individuals that could specifically bind to and agglutinate bacteria.
Scientists now know the cause of the agglutination is an antibody molecule, also called an immunoglobulin . What is an antibody? An antibody protein is essentially a secreted form of a B cell receptor. (In fact, surface immunoglobulin is another name for the B cell receptor.) Not surprisingly, the same genes encode both the secreted antibodies and the surface immunoglobulins. One minor difference in the way these proteins are synthesized distinguishes a naïve B cell with antibody on its surface from an antibody-secreting plasma cell with no antibodies on its surface. The antibodies of the plasma cell have the exact same antigen-binding site and specificity as their B cell precursors.
There are five different classes of antibody found in humans: IgM, IgD, IgG, IgA, and IgE. Each of these has specific functions in the immune response, so by learning about them, researchers can learn about the great variety of antibody functions critical to many adaptive immune responses.
B cells do not recognize antigen in the complex fashion of T cells. B cells can recognize native, unprocessed antigen and do not require the participation of MHC molecules and antigen-presenting cells.
B Cell Differentiation and Activation
B cells differentiate in the bone marrow. During the process of maturation, up to 100 trillion different clones of B cells are generated, which is similar to the diversity of antigen receptors seen in T cells.
B cell differentiation and the development of tolerance are not quite as well understood as it is in T cells. Central tolerance is the destruction or inactivation of B cells that recognize self-antigens in the bone marrow, and its role is critical and well established. In the process of clonal deletion , immature B cells that bind strongly to self-antigens expressed on tissues are signaled to commit suicide by apoptosis, removing them from the population. In the process of clonal anergy , however, B cells exposed to soluble antigen in the bone marrow are not physically deleted, but become unable to function.
Another mechanism called peripheral tolerance is a direct result of T cell tolerance. In peripheral tolerance , functional, mature B cells leave the bone marrow but have yet to be exposed to self-antigen. Most protein antigens require signals from helper T cells (Th2) to proceed to make antibody. When a B cell binds to a self-antigen but receives no signals from a nearby Th2 cell to produce antibody, the cell is signaled to undergo apoptosis and is destroyed. This is yet another example of the control that T cells have over the adaptive immune response.
After B cells are activated by their binding to antigen, they differentiate into plasma cells. Plasma cells often leave the secondary lymphoid organs, where the response is generated, and migrate back to the bone marrow, where the whole differentiation process started. After secreting antibodies for a specific period, they die, as most of their energy is devoted to making antibodies and not to maintaining themselves. Thus, plasma cells are said to be terminally differentiated.
The final B cell of interest is the memory B cell, which results from the clonal expansion of an activated B cell. Memory B cells function in a way similar to memory T cells. They lead to a stronger and faster secondary response when compared to the primary response, as illustrated below.
Antibody Structure
Antibodies are glycoproteins consisting of two types of polypeptide chains with attached carbohydrates. The heavy chain and the light chain are the two polypeptides that form the antibody. The main differences between the classes of antibodies are in the differences between their heavy chains, but as you shall see, the light chains have an important role, forming part of the antigen-binding site on the antibody molecules.
Four-chain Models of Antibody Structures
All antibody molecules have two identical heavy chains and two identical light chains. (Some antibodies contain multiple units of this four-chain structure.) The Fc region of the antibody is formed by the two heavy chains coming together, usually linked by disulfide bonds (Figure \(\PageIndex{1}\)). The Fc portion of the antibody is important in that many effector cells of the immune system have Fc receptors. Cells having these receptors can then bind to antibody-coated pathogens, greatly increasing the specificity of the effector cells. At the other end of the molecule are two identical antigen-binding sites.
Five Classes of Antibodies and their Functions
In general, antibodies have two basic functions. They can act as the B cell antigen receptor or they can be secreted, circulate, and bind to a pathogen, often labeling it for identification by other forms of the immune response. Of the five antibody classes, notice that only two can function as the antigen receptor for naïve B cells: IgM and IgD (Figure \(\PageIndex{2}\)). Mature B cells that leave the bone marrow express both IgM and IgD, but both antibodies have the same antigen specificity. Only IgM is secreted, however, and no other nonreceptor function for IgD has been discovered.
IgM consists of five four-chain structures (20 total chains with 10 identical antigen-binding sites) and is thus the largest of the antibody molecules. IgM is usually the first antibody made during a primary response. Its 10 antigen-binding sites and large shape allow it to bind well to many bacterial surfaces. It is excellent at binding complement proteins and activating the complement cascade, consistent with its role in promoting chemotaxis, opsonization, and cell lysis. Thus, it is a very effective antibody against bacteria at early stages of a primary antibody response. As the primary response proceeds, the antibody produced in a B cell can change to IgG, IgA, or IgE by the process known as class switching. Class switching is the change of one antibody class to another. While the class of antibody changes, the specificity and the antigen-binding sites do not. Thus, the antibodies made are still specific to the pathogen that stimulated the initial IgM response.
IgG is a major antibody of late primary responses and the main antibody of secondary responses in the blood. This is because class switching occurs during primary responses. IgG is a monomeric antibody that clears pathogens from the blood and can activate complement proteins (although not as well as IgM), taking advantage of its antibacterial activities. Furthermore, this class of antibody is the one that crosses the placenta to protect the developing fetus from disease exits the blood to the interstitial fluid to fight extracellular pathogens.
IgA exists in two forms, a four-chain monomer in the blood and an eight-chain structure, or dimer, in exocrine gland secretions of the mucous membranes, including mucus, saliva, and tears. Thus, dimeric IgA is the only antibody to leave the interior of the body to protect body surfaces. IgA is also of importance to newborns, because this antibody is present in mother’s breast milk (colostrum), which serves to protect the infant from disease.
IgE is usually associated with allergies and anaphylaxis. It is present in the lowest concentration in the blood, because its Fc region binds strongly to an IgE-specific Fc receptor on the surfaces of mast cells. IgE makes mast cell degranulation very specific, such that if a person is allergic to peanuts, there will be peanut-specific IgE bound to his or her mast cells. In this person, eating peanuts will cause the mast cells to degranulate, sometimes causing severe allergic reactions, including anaphylaxis, a severe, systemic allergic response that can cause death.
Clonal Selection of B Cells
Clonal selection and expansion work much the same way in B cells as in T cells. Only B cells with appropriate antigen specificity are selected for and expanded (Figure \(\PageIndex{3}\)). Eventually, the plasma cells secrete antibodies with antigenic specificity identical to those that were on the surfaces of the selected B cells. Notice in the figure that both plasma cells and memory B cells are generated simultaneously.
Primary versus Secondary B Cell Responses
Primary and secondary responses as they relate to T cells were discussed earlier. This section will look at these responses with B cells and antibody production. Because antibodies are easily obtained from blood samples, they are easy to follow and graph (Figure \(\PageIndex{4}\)). As you will see from the figure, the primary response to an antigen (representing a pathogen) is delayed by several days. This is the time it takes for the B cell clones to expand and differentiate into plasma cells. The level of antibody produced is low, but it is sufficient for immune protection. The second time a person encounters the same antigen, there is no time delay, and the amount of antibody made is much higher. Thus, the secondary antibody response overwhelms the pathogens quickly and, in most situations, no symptoms are felt. When a different antigen is used, another primary response is made with its low antibody levels and time delay.
Active versus Passive Immunity
Immunity to pathogens, and the ability to control pathogen growth so that damage to the tissues of the body is limited, can be acquired by (1) the active development of an immune response in the infected individual or (2) the passive transfer of immune components from an immune individual to a nonimmune one. Both active and passive immunity have examples in the natural world and as part of medicine.
Active immunity is the resistance to pathogens acquired during an adaptive immune response within an individual (Table). Naturally acquired active immunity, the response to a pathogen, is the focus of this chapter. Artificially acquired active immunity involves the use of vaccines. A vaccine is a killed or weakened pathogen or its components that, when administered to a healthy individual, leads to the development of immunological memory (a weakened primary immune response) without causing much in the way of symptoms. Thus, with the use of vaccines, one can avoid the damage from disease that results from the first exposure to the pathogen, yet reap the benefits of protection from immunological memory. The advent of vaccines was one of the major medical advances of the twentieth century and led to the eradication of smallpox and the control of many infectious diseases, including polio, measles, and whooping cough.
| Active versus Passive Immunity | ||
|---|---|---|
| Natural | Artificial | |
| Active | Adaptive immune response | Vaccine response |
| Passive | Trans-placental antibodies/breastfeeding | Immune globulin injections |
Passive immunity arises from the transfer of antibodies to an individual without requiring them to mount their own active immune response. Naturally acquired passive immunity is seen during fetal development. IgG is transferred from the maternal circulation to the fetus via the placenta, protecting the fetus from infection and protecting the newborn for the first few months of its life. As already stated, a newborn benefits from the IgA antibodies it obtains from milk during breastfeeding. The fetus and newborn thus benefit from the immunological memory of the mother to the pathogens to which she has been exposed. In medicine, artificially acquired passive immunity usually involves injections of immunoglobulins, taken from animals previously exposed to a specific pathogen. This treatment is a fast-acting method of temporarily protecting an individual who was possibly exposed to a pathogen. The downside to both types of passive immunity is the lack of the development of immunological memory. Once the antibodies are transferred, they are effective for only a limited time before they degrade.
Immunity can be acquired in an active or passive way, and it can be natural or artificial. Watch this video to see an animated discussion of passive and active immunity. What is an example of natural immunity acquired passively?
T cell-dependent versus T cell-independent Antigens
As discussed previously, Th2 cells secrete cytokines that drive the production of antibodies in a B cell, responding to complex antigens such as those made by proteins. On the other hand, some antigens are T cell independent. A T cell-independent antigen usually is in the form of repeated carbohydrate moieties found on the cell walls of bacteria. Each antibody on the B cell surface has two binding sites, and the repeated nature of T cell-independent antigen leads to crosslinking of the surface antibodies on the B cell. The crosslinking is enough to activate it in the absence of T cell cytokines.
A T cell-dependent antigen , on the other hand, usually is not repeated to the same degree on the pathogen and thus does not crosslink surface antibody with the same efficiency. To elicit a response to such antigens, the B and T cells must come close together (Figure \(\PageIndex{5}\)). The B cell must receive two signals to become activated. Its surface immunoglobulin must recognize native antigen. Some of this antigen is internalized, processed, and presented to the Th2 cells on a class II MHC molecule. The T cell then binds using its antigen receptor and is activated to secrete cytokines that diffuse to the B cell, finally activating it completely. Thus, the B cell receives signals from both its surface antibody and the T cell via its cytokines, and acts as a professional antigen-presenting cell in the process.
Chapter Review
B cells, which develop within the bone marrow, are responsible for making five different classes of antibodies, each with its own functions. B cells have their own mechanisms for tolerance, but in peripheral tolerance, the B cells that leave the bone marrow remain inactive due to T cell tolerance. Some B cells do not need T cell cytokines to make antibody, and they bypass this need by the crosslinking of their surface immunoglobulin by repeated carbohydrate residues found in the cell walls of many bacterial species. Others require T cells to become activated.
Interactive Link Questions
Immunity can be acquired in an active or passive way, and it can be natural or artificial. Watch this video to see an animated discussion of passive and active immunity. What is an example of natural immunity acquired passively?
Answer: Breastfeeding is an example of natural immunity acquired passively.
Review Chapter
Q. Removing functionality from a B cell without killing it is called ________.
A. clonal selection
B. clonal expansion
C. clonal deletion
D. clonal anergy
Answer: D
Q. Which class of antibody crosses the placenta in pregnant women?
A. IgM
B. IgA
C. IgE
D. IgG
Answer: D
Q. Which class of antibody has no known function other than as an antigen receptor?
A. IgM
B. IgA
C. IgE
D. IgD
Answer: D
Q. When does class switching occur?
A. primary response
B. secondary response
C. tolerance
D. memory response
Answer: A
Q. Which class of antibody is found in mucus?
A. IgM
B. IgA
C. IgE
D. IgD
Answer: B
Critical Thinking Questions
Q. Describe how secondary B cell responses are developed.
A. B cells activated during a primary response differentiate either into terminally differentiated plasma cells or into memory B cells. These memory B cells are what respond during a secondary or memory antibody response.
Q. Describe the role of IgM in immunity.
A. IgM is an antigen receptor on naïve B cells. Upon activation, naïve B cells make IgM first. IgM is good at binding complement and thus has good antibacterial effects. IgM is replaced with other classes of antibodies later on in the primary response due to class switching.
Glossary
- active immunity
- immunity developed from an individual’s own immune system
- central tolerance
- B cell tolerance induced in immature B cells of the bone marrow
- class switching
- ability of B cells to change the class of antibody they produce without altering the specificity for antigen
- clonal anergy
- process whereby B cells that react to soluble antigens in bone marrow are made nonfunctional
- clonal deletion
- removal of self-reactive B cells by inducing apoptosis
- Fc region
- in an antibody molecule, the site where the two termini of the heavy chains come together; many cells have receptors for this portion of the antibody, adding functionality to these molecules
- heavy chain
- larger protein chain of an antibody
- IgA
- antibody whose dimer is secreted by exocrine glands, is especially effective against digestive and respiratory pathogens, and can pass immunity to an infant through breastfeeding
- IgD
- class of antibody whose only known function is as a receptor on naive B cells; important in B cell activation
- IgE
- antibody that binds to mast cells and causes antigen-specific degranulation during an allergic response
- IgG
- main blood antibody of late primary and early secondary responses; passed from mother to unborn child via placenta
- IgM
- antibody whose monomer is a surface receptor of naive B cells; the pentamer is the first antibody made blood plasma during primary responses
- immunoglobulin
- protein antibody; occurs as one of five main classes
- light chain
- small protein chain of an antibody
- passive immunity
- transfer of immunity to a pathogen to an individual that lacks immunity to this pathogen usually by the injection of antibodies
- peripheral tolerance
- mature B cell made tolerant by lack of T cell help
- T cell-dependent antigen
- antigen that binds to B cells, which requires signals from T cells to make antibody
- T cell-independent antigen
- binds to B cells, which do not require signals from T cells to make antibody


27.2: Scientific writing
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Scientific writing is important in communicating with other scientists. Think of scientific writing as a style of writing where every word counts . It makes for rather “dry” reading, but it is important for clearly and precisely communicating factual information. The main guidelines for scientific writing are be concise, precise, factual, and clear . Below are some tips to help with scientific writing:
- Avoid subjective/imprecise terms: avoid using subjective and imprecise terms, stick to factual statements and avoid opinions. Instead of saying “our calculated value of g was much greater than the expected value”, say “our calculated value of g was greater than the expected value”. Your opinion that it was ”much greater” does not communicate anything and is imprecise (much greater in relation to what?).
- Definitive statements: avoid attributing definitive causes to your experimental outcomes. You can never prove a theory to be correct, so at most, your results will be consistent with a theory. For example, instead of saying “as the data exhibit, we have detected the Purple Particle”, you should state that “the data are consistent with the detection of the Purple Particle”.
- Data is the plural of datum. “This data shows” is incorrect, rather, “these data show”, or “this set of data shows”.
- Active vs. passive voice: when writing scientific papers, it is recommended to use the third person, passive voice. For example, this would mean saying “the drop time for balls at various heights was measured” rather than “we measured the drop time for balls at various heights”. However, both passive and active voices are acceptable in scientific writing, as long as it is consistent throughout the text.
- Tense. Generally, for a proposal, you would use the future tense, and you would use the past tense for reporting on your results.
emma's thoughts
Writing and editing - how can I be more concise? We’ve all felt that our writing was lacking at some point or another. Here are some general tips to avoid overall “wordiness” and to increase ease of reading when writing scientifically:
- What would you want to read? Let’s say that you wanted to know the strength of Earth’s magnetic field, and how it was found, so you decide to do a literature search. Would you choose a brief, succinct article, or a wordy Magnetic Field Manifesto?
- The kindergarten test: If you had to explain your concept to a six year old cousin, how would you break it down in a way that they could understand it? If you can’t break it down enough to explain to a six year old, perhaps you need to revisit your own understanding of the concept before writing about it scientifically.
- Avoid unnecessary adjectives: while this might be ok in a creative writing class, in scientific writing, the goal is to get your point across as succinctly as possible. Using “big” words might be ok (as long as they properly describe what you are trying to say), but it is important to communicate your message in the simplest manner.
- Think about it: every time you use a comma, dash or even an “and”, you should reconsider the brevity of your statement. In scientific writing, commas are carefully placed, and semicolons are rare.
- Cut it in half: For every word you read, think of another that you can cut. For every sentence that you read, think of three sentences that communicate the same idea. Pick the sentence that is the shortest and most concise.
- Proofread - the more, the better.
The following sections provide basic outlines for writing a proposal and a lab report, as well as rubrics for evaluating/reviewing proposals and reports. Additionally, samples of a proposal, proposal review, report, and report review for the experiment “Measuring g using a pendulum” are provided. In the sample proposal and lab report, errors are purposefully included and addressed in the reviews. It is important to entirely read the rest of this section to capture the common proposal/lab mistakes and their corresponding corrections. That is, do not take the sample proposal as a “perfect proposal”, but rather, consider it in the light of the corresponding review.


5.1.3: Things to Consider When Managing Teams
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Learning Objectives
- What are some key considerations in managing teams?
For those of us who have had the pleasure of managing or leading a team, we know that it can feel like a dubious distinction. Leading a team is fulfilling—especially if the task or organizational mandate at hand is so critical to the organization that people are happy to be a part of the team that drives things forward. It can also be an exercise in frustration, as the charge is to lead a group composed of various individuals, which at various times will act both like a group and like a bunch of individuals. Managing teams is no small feat, and the most experience managers truly understand that success ultimately depends on their ability to build a strong and well-functioning team. In J.J. Gabarro’s The Dynamics of Taking Charge (HBS Press, 1987, pp. 85–87), he quotes a manager who had successfully worked to turn around a number of organizations: 4
“People have to want to work together; they have to see how to do it. There has to be an environment for it and that takes time. It’s my highest priority right now but I don’t write it down anywhere because it’s not like other priorities. If I told corporate that building a team was my prime goal they’d tell me, so what? They’d expect that as part of making things better.”
I love this quotation because it’s so indicative of the state of most organizations today. The focus is on corporate goals and priorities—very task-driven and outcome-driven—but it is the people dynamics and how people work together in the company and in TEAMS that can make a real difference to the goals and outcome.
MANAGERIAL LEADERSHIP
Who Am I Managing?
Making the jump from individual contributor to manager is never easy, and it doesn’t take long for a new manager to realize that what got him there is much different than what is needed to be successful in the future. Individual contributors that have been recently promoted would probably say that they have strong technical skills in their area, and that they were very good at doing what they were doing. In a more savvy organization that recognizes leadership competencies, individual contributors would probably say that they have strong technical skills AND that they showed some behaviors and potential to lead others. When new managers enter their new roles, they expect that they will be managing people—that is, the people on their teams. Few new managers fully realize that the challenge ahead is not just in managing their people, but in managing all the other stakeholders and constituencies that want to and need to weigh in.
One of the key challenges that faces new managers is figuring out to balance all of the multiple demands from both the team and the stakeholders and constituencies external to the team. Linda A. Hill, the Wallace Brett Donham Professor of Business Administration at Harvard Business School, states that “among all the challenges facing new managers, the need to reconcile different constituencies’ expectations and interests is probably the most difficult.” She asserts that the demands that the new manager’s direct reports, his peers, his boss, and the company’s customers place on the new manager will cause conflict at times. Having teams of their own, new managers may think that managing their direct reports is the most important role to play, even at the exclusion of managing other stakeholders. This is incorrect. A new manager needs to “manage his other consistencies just as carefully.” (“Helping New Managers Succeed,” Lauren Keller Johnson, HBR 2008).
Whenever I started a new role, I always created a quick stakeholder checklist for myself. This document is essentially a list of all the stakeholders (beyond the team I am managing) with whom I need to build a relationship in order to be successful. I listed the names of my boss, my boss’s boss, my peers, and any other key influencers or internal customers from the business. This is a quick checklist of the people that I need to immediately have a “meet and greet” with and then possibly even set up a regular meeting with at a certain cadence. I have learned over the years that each of these stakeholders will have some input and impact on my success, and the quicker and more effectively I engage them in the work my team is performing, the better the chance of my team’s success. Some of the questions I will ask myself when figuring out my stakeholder list include:
- Whose support will I need?
- Who needs my support? What do they need from me or my team?
- Who can keep me and my team from being successful?
- What is my ongoing influencing strategy?
Some new managers will feel that these strategies for building stakeholder support are too “political” and they don’t feel right. Trust me when I tell you that this is a necessary part of the new manager role, because now the role and the work call for greater interdependence and relation building in order to be successful. It is no longer just about individual technical skills, but more about building and managing relationships with people who will support you and your team to get your work done. So, if you are a new manager asking “Who am I managing?” … the answer is EVERYONE.
discussion questions
- Do you agree with the statement that “what got you there isn’t what will make you successful in the future”? Why or why not?
- Who would be on your stakeholder checklist? Which stakeholders are you already engaging and building relationships with?
In Linda A. Hill’s Harvard Business Review article “Managing Your Team” 5 (HBR 1995), she discusses that managing a team means managing paradox. Paradox exists in the fact that teams have both individual and collective identities and goals. Each individual has goals and ideas as to what he wants to accomplish—on the project, in one’s career, and in life. The team itself, of course, has goals and success metrics that it needs to meet in order to be successful. Sometimes these can be in conflict with each other. Competition may arise among team members, and a win-loss attitude may take place over a collaborative and problem-solving team dynamic. The team manager may need to step in to help integrate all of the individual differences to enable them to productively pursue the team goal. Therein lies the primary paradox—balancing individual differences and goals AND the collective identity and goals. Other paradoxes include:
- Fostering support AND confrontation among team members
- Focusing on performance AND learning and development
- Balancing managerial authority AND team member discretion and autonomy
- Balancing the Triangle of Relationships—manager, team, and individual
Managing a team also means managing its boundaries. Managing the team’s boundaries—or space between the team and its external forces, stakeholders, and pressures—is a delicate balance of strategy, stakeholder management, and organizational behavior. The team manager must serve, in part, as a buffer to these external factors so that they don’t derail or distract the team from its goals. However, the manager must also understand enough about the external environment and have enough emotional intelligence to understand which forces, players, or situations must be synthesized within the team for its own benefit. Think about any medium or large-scale change initiative that you have been a part of in your career. Ideally, there is generally a vision for change and a level of sponsorship at the senior levels of the organization that is supposed to pave the way for that change to take root. The project team is officially “blessed” to kick off the team, create a charter, and identify the needed actions to drive the initiative to successful completion.
The dynamic that ensues after the kickoff is really what will determine the success of the team. There are numerous stakeholders in any organization, and many will be pro-change initiative, but others may be against the initiative—either due to lack of understanding or concerns about losing power, territory, etc. The external environment and business strategy may not be particularly well suited for a change initiative to take place, and so there may be the feeling of forces opposing the project team efforts. A strong team manager needs manage these “boundaries” with the organization to help the team navigate through and with the organizational complexities, goals, nuances, and egos that are a part of any organization. In Linda A. Hill’s Harvard Business Review article “Exercising Influence,” she states that “managers also need to manage relationships with those who are outside their team but inside their organizations. 6 To do so, they must understand the power dynamics of the larger organization and invest time and energy in building and maintaining relationship with those on who the team is dependent.” It is also, in her view, “the manager’s job, at a minimum, to educate other about organizational structures, systems, or politics that interfere with the team’s performance.” With all of the potential external influences on a team, managing a team’s boundaries can truly mean the difference between success and failure.
The final element of managing a team is to manage the team itself—both the people elements and the process elements, or task at hand. The process-focused elements include managing the work plan to reach the overall goal, as well as the incremental meetings and milestones that are a part of the team’s journey to reach the longer-term goal. Keeping the team focused on its objectives—beginning with setting agendas all the way to managing project tasks and celebrating milestones—assures that the team will stay on track. Projects and initiatives vary in size, scope, and complexity, and so the project management tools shouldn’t be prescribed in a general sense. The important takeaway here is to choose an approach and a tool that works for the culture of the team and the organization, and that helps the team understand where they are, where they need to go, and what resources are a part of that process.
In managing the team members and interpersonal dynamics, there is the important element of selecting the right team members, shaping the team’s norms and culture (how are decisions made, what are our rules, how do we manage conflict, etc.), and coaching the team. Defining the right skill sets, functions, perspectives, and expertise of the members will ensure a solid foundation. Helping the team to identify and formalize the ground rules for team engagement will help manage in the face of adversity or team conflict in the future. Finally, playing a role as a supportive coach will help both the individual team members and the group entity think through issues and make progress towards goals. A coach doesn’t solve the individual/team problem, but helps the team think through a solution and move forward. Teams may need guidance on how to work things out within the team, and the manager must provide feedback and hold team members accountable for their behavior and contribution. Continuous improvement is the name of the game. A team may not start out as high performing, but they can certainly achieve that goal if everyone is focused on incremental improvements to communication, collaboration, and performance.
concept check
- Discuss the paradox(es) of a team.
- How can a leader manage team boundaries?


6.2: Choosing Loans and Managing Debt Wisely
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If you find yourself in the market for a credit card or loan, take time to fully understand the terms and conditions before you apply. Knowing what the monthly payments will be and ensuring they fit comfortably into your budget also is crucial.
How to Choose a Credit Card or Other Loan
If you’re considering opening a credit card or taking on another loan, such as a car loan or personal line of credit, there are several factors to consider.
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Lender - Before applying for a credit card or loan, research the lender and make sure the company is reputable. To apply for a loan, you’ll likely have to share personal and financial information that you don’t want to end up in the wrong hands.
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APR - The APR, or Annual Percentage Rate, of a credit card or loan is the rate at which interest will accrue on the balance you carry. The APR can be fixed or variable.
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Fixed – The interest rate remains the same during the fixed rate period of the loan
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Variable – The interest rate can change over time, usually fluctuating with the market
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Fees – There are many possible fees you’ll want to be aware of before opening any loan. One of the most common is a late payment fee which is what you’ll be charged if you don’t pay your bill on time. Some credit cards carry other fees you’ll want to be aware of, such as:
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Annual fee - A yearly charge for having an open credit card account
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Cash advance fee - A charge for using your credit card to withdraw cash (i.e. at an ATM)
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Foreign transaction fee - A charge for using your card out of the country
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Balance transfer fee - A charge for moving a balance from one credit card to another
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Benefits - Some lenders may offer consumer perks for those who use their loan products. Examples of this include free credit score monitoring services for borrowers or rental car insurance if the rental is paid for with the corresponding credit card.
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Planned card usage - When looking at credit cards specifically, you’ll want to consider what you’ll use the card for before applying
Using and Managing Debt Responsibly
Having debt can impact your financial life in many ways from needing to make monthly payments to affecting your credit score, which raises the question - is all debt created equal ?
The answer is no. Some debt is commonly considered “good” while other debt is looked upon less favorably. One way to distinguish between these two types is to look at what the debt does for you. Some forms of debt let you achieve your goals, such as attending college or buying a car or home. Other debt keeps you stuck in the past or creates patterns of harmful financial behavior, such as living outside of your means and carrying a high balance on a credit card.
Avoiding “Bad” Debt
Knowing the difference between debt that benefits you and debt that gets in the way can help you plan your finances and set goals. Knowing what you can do to avoid bad debt can also help you as you work toward achieving financial success.
Here’s what to pay attention to and do to keep bad debt out of your life:
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Create a budget. The first step to avoiding bad debt is knowing what you can and can’t afford each month. Calculate how much you earn monthly, then subtract your fixed expenses from your income to see if you have any discretionary income.
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Fixed expenses - expenses that stay the same and do not vary from month to month (car loan, mortgage payment, rent payment, etc.).
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Variable expenses - expenses that change over time (electric bill, dining out expenses, credit card payments, etc.).
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Build up an emergency fund . Payday lenders promise that they’ll help you out in a pinch. But their “help” is super expensive, due to high interest and fees, and can make a tough situation even more challenging. If you can save up an emergency fund , even just a few hundred dollars, you have something to fall back on when money is tight.
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Be cautious of interest rates . How much you pay in interest can make a good debt bad or a bad debt even worse. Shop around when looking for loans or credit cards to get the lowest rate possible.
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Consider the value the loan provides . Before you borrow money, consider the long-term value of the loan. With a mortgage, you may be spending hundreds of thousands of dollars, but you end up with a forever home. In terms of student loan debt , you might not be able to pursue your desired career without borrowing money. With credit card debt, not being able to pay off the entire amount you borrow right away can end up costing you even more without any real benefits for you.
- Try to keep your overall debt low . Lenders often talk about the debt-to-income ratio. That ration is how much you pay each month compared to your income. The lower your debt-to-income ratio, the more financially comfortable you can be. If you have a lot of debt already, whether it’s good debt or bad debt, it’s a good idea to consider how taking on an additional loan would add to your debt-to-income ratio. If your ratio is over 43 % , paying off debt can be challenging.
Paying Down Debt
Typically, one of the best ways to eliminate debt is to make more than the minimum payment whenever you can. Even adding a small amount to your required payment each month can make a big difference.
The example below demonstrates how adding to your minimum payment each month can help you not only pay off a credit card balance sooner, but also save money on interest over time.
Debt Repayment Strategies
How you tackle your debt repayment should be based on your specific situation. Two common options are the debt avalanche and debt snowball methods .
The debt avalanche method has you focus on paying off the loan with the highest interest rate first – just like how an avalanche starts at the peak and tumbles downward. This method allows you to save the most money on interest in the long run. Here’s how the debt avalanche works:
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List all your debts from highest interest rate to lowest interest rate without listing the balances.
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Make the required minimum payment on all debts
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Put any extra money toward the debt with the highest interest rate.
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Once the highest interest rate debt is paid off, take that former payment, as well as any extra money, and apply it to the next highest interest rate debt.
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Continue until all debts are paid off.
The debt snowball method has you focus on paying down your smallest debts first and then work to eliminate larger ones – just as a snowball starts small and gets bigger and bigger. While you won’t save you as much in interest payments, the quick wins of eliminating payments can help you stay motivated to continue. Here’s how the debt snowball works:
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List all your debts in order from lowest to highest balance without listing interest rates.
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Make the required minimum payment on all debts.
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Put any extra money toward the debt with the lowest balance owed.
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Once the lowest balance debt is paid off, apply that payment and any extra money to the next lowest balance debt.
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Continue until all debts are paid off.
If you’re concerned about a high balance on one account, you might focus on that debt first, even if that account isn’t your smallest loan or highest interest debt.


Young children’s development can be conceptualized in four main areas: physical, intellectual, emotional, and social.
Understanding how children develop is important to ensure healthy developmental progression.
While there are many commonalities, there are also individual and cultural differences in development such that development is not identical for each child.
High-quality classroom settings and practices should support individual and cultural developmental needs.
Terminology Found Throughout this Chapter
Atypical development:
When a child does not develop in the way that is congruent with averages for a given age, causing a disturbance to everyday activities.
Child development:
The pattern of change that begins at conception and continues through adolescence.
Culturally relevant pedagogy
: The practice of including ideas and artifacts that refer to a child’s individual culture.
Developmentally appropriate practice:
Methods that promote each child’s optimal development and learning through a strengths-based, play-based approach to joyful, engaged learning.
Developmental domains:
Specific areas in which growth occurs – Physical, Cognitive, Emotional, and Social.
Differentiation
: The thoughtful practice of tailoring activities to meet children’s individual needs.
Early childhood period:
Ages birth through age eight.
Executive function:
Collection of processes that encompass attention, working memory, and inhibition.
Fine motor skills:
Movement related to small muscle groups in the body.
Gross motor skills:
Movement related to the large muscle groups in the body.
Joint attention:
The action of a child and a caregiver focusing on the same object or concept at the same time.
Metacognition:
Self-reflection; an ability to think about one’s own thoughts.
Open-ended questions:
Questions that do not have a yes or no answer.
Separation anxiety:
A fear of being separated from their primary caregiver.
Temperament:
An infant’s regular way of reacting with their environment.
Toxic stress:
Physical or emotional abuse, neglect, witnessing of physical or emotional abuse of another person, or extreme poverty.
Typical development
: When a child develops in the way that is congruent with averages for a given age.


6.4: Molarity
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Learning Objectives
By the end of this section, you will be able to:
- Describe the fundamental properties of solutions
- Calculate solution concentrations using molarity
- Perform dilution calculations using the dilution equation
Preceding sections of this chapter focused on the composition of substances: samples of matter that contain only one type of element or compound. However, mixtures—samples of matter containing two or more substances physically combined—are more commonly encountered in nature than are pure substances. Similar to a pure substance, the relative composition of a mixture plays an important role in determining its properties. The relative amount of oxygen in a planet’s atmosphere determines its ability to sustain aerobic life. The relative amounts of iron, carbon, nickel, and other elements in steel (a mixture known as an “alloy”) determine its physical strength and resistance to corrosion. The relative amount of the active ingredient in a medicine determines its effectiveness in achieving the desired pharmacological effect. The relative amount of sugar in a beverage determines its sweetness (see Figure \(\PageIndex{1}\)). This section will describe one of the most common ways in which the relative compositions of mixtures may be quantified.
Solutions
Solutions have previously been defined as homogeneous mixtures, meaning that the composition of the mixture (and therefore its properties) is uniform throughout its entire volume. Solutions occur frequently in nature and have also been implemented in many forms of manmade technology. A more thorough treatment of solution properties is provided in the chapter on solutions and colloids, but provided here is an introduction to some of the basic properties of solutions.
The relative amount of a given solution component is known as its concentration . Often, though not always, a solution contains one component with a concentration that is significantly greater than that of all other components. This component is called the solvent and may be viewed as the medium in which the other components are dispersed, or dissolved . Solutions in which water is the solvent are, of course, very common on our planet. A solution in which water is the solvent is called an aqueous solution .
A solute is a component of a solution that is typically present at a much lower concentration than the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
Concentrations may be quantitatively assessed using a wide variety of measurement units, each convenient for particular applications. Molarity ( M ) is a useful concentration unit for many applications in chemistry. Molarity is defined as the number of moles of solute in exactly 1 liter (1 L) of the solution:
\[M=\frac{\text { mol solute }}{\text { L solution }} \nonumber \]
Example \(\PageIndex{1}\): Calculating Molar Concentrations
A 355-mL soft drink sample contains 0.133 mol of sucrose (table sugar). What is the molar concentration of sucrose in the beverage?
Solution
Since the molar amount of solute and the volume of solution are both given, the molarity can be calculated using the definition of molarity. Per this definition, the solution volume must be converted from mL to L:
\[M=\frac{\text { mol solute }}{ \text{L}\, \text{solution}}=\frac{0.133\,\text{mol}}{355\,\text{mL} \times \frac{1\,\text{L} }{1000 \,\text{mL} }}=0.375 M \nonumber \]
Exercise \(\PageIndex{1}\)
A teaspoon of table sugar contains about 0.01 mol sucrose. What is the molarity of sucrose if a teaspoon of sugar has been dissolved in a cup of tea with a volume of 200 mL?
- Answer
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0.05 M
Example \(\PageIndex{2}\): Deriving Moles and Volumes from Molar Concentrations
How much sugar (mol) is contained in a modest sip (~10 mL) of the soft drink from Example \(\PageIndex{1}\)?
Solution
Rearrange the definition of molarity to isolate the quantity sought, moles of sugar, then substitute the value for molarity derived in Example \(\PageIndex{1}\), 0.375 M :
\[\begin{align*}
M&=\dfrac{\text { mol solute }}{ L \text { solution }} \\[4pt]
\text { mol solute } &=M \times L \text { solution } \\[4pt]
&=0.375 \frac{\text { mol sugar }}{ L } \times\left(10\, \text{mL} \times \frac{1\,\text{L}}{1000\,\text{mL}}\right)\\[4pt]&=0.004\, \text{mol} \, \text{sugar }
\end{align*} \nonumber \]
Exercise \(\PageIndex{2}\)
What volume (mL) of the sweetened tea described in Example \(\PageIndex{1}\) contains the same amount of sugar (mol) as 10 mL of the soft drink in this example?
- Answer
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80 mL
Example \(\PageIndex{3}\): Calculating Molar Concentrations from the Mass of Solute
Distilled white vinegar (Figure \(\PageIndex{2}\)) is a solution of acetic acid, CH 3 CO 2 H, in water. A 0.500-L vinegar solution contains 25.2 g of acetic acid. What is the concentration of the acetic acid solution in units of molarity?
Solution
As in previous examples, the definition of molarity is the primary equation used to calculate the quantity sought. Since the mass of solute is provided instead of its molar amount, use the solute’s molar mass to obtain the amount of solute in moles:
\[M=\frac{\text { mol solute }}{\text { L solution }}=\frac{25.2\,\text{g}\,\ce{CH3CO2H} \times \frac{1\,\text{mol]}\,\ce{CH3CO2H} }{60.052 \,\text{g}\,\ce{CH3CO2H}}}{0.500\,\text{L}\, \text{solution }}=0.839\, \text{M} \nonumber \]
Exercise \(\PageIndex{3}\)
Calculate the molarity of 6.52 g of CoCl 2 (128.9 g/mol) dissolved in an aqueous solution with a total volume of 75.0 mL.
- Answer
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0.674 M
Example \(\PageIndex{4}\): Determining the Mass of Solute in a Given Volume of Solution
How many grams of NaCl are contained in 0.250 L of a 5.30- M solution?
Solution
The volume and molarity of the solution are specified, so the amount (mol) of solute is easily computed as demonstrated in Example \(\PageIndex{2}\):
\[\begin{align*}
M &=\frac{\text { mol solute }}{ L \text { solution }} \\[4pt]
\text { mol solute } &=M \times L \text { solution } \\[4pt]
&=5.30 \frac{ \text{mol}\, \ce{NaCl} }{ \text{L}} \times 0.250 L \\[4pt]
& =1.325\, \text{mol}\,\ce{NaCl}
\end{align*} \nonumber \]
Finally, this molar amount is used to derive the mass of NaCl:
\[1.325\, \text{mol}\, \ce{NaCl} \times \dfrac{58.44\, \text{g}\, \ce{NaCl}}{ 1 \, \text{mol}\, \ce{NaCl}} = 77.4 \, \text{g}\, \ce{NaCl} \nonumber \]
Exercise \(\PageIndex{4}\)
How many grams of CaCl 2 (110.98 g/mol) are contained in 250.0 mL of a 0.200- M solution of calcium chloride?
- Answer
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5.55 g CaCl 2
When performing calculations stepwise, as in Example \(\PageIndex{4}\), it is important to refrain from rounding any intermediate calculation results, which can lead to rounding errors in the final result. In Example \(\PageIndex{4}\), the molar amount of NaCl computed in the first step, 1.325 mol, would be properly rounded to 1.32 mol if it were to be reported; however, although the last digit (5) is not significant, it must be retained as a guard digit in the intermediate calculation. If the guard digit had not been retained, the final calculation for the mass of NaCl would have been 77.1 g, a difference of 0.3 g.
In addition to retaining a guard digit for intermediate calculations, rounding errors may also be avoided by performing computations in a single step (see Example \(\PageIndex{5}\)). This eliminates intermediate steps so that only the final result is rounded.
Example \(\PageIndex{5}\): Determining the Volume of Solution Containing a Given Mass of Solute
In Example \(\PageIndex{3}\), the concentration of acetic acid in white vinegar was determined to be 0.839 M . What volume of vinegar contains 75.6 g of acetic acid?
Solution
First, use the molar mass to calculate moles of acetic acid from the given mass:
\[\text { g solute } \times \frac{\text { mol solute }}{\text { g solute }}=\text { mol solute } \nonumber \]
Then, use the molarity of the solution to calculate the volume of solution containing this molar amount of solute:
\[\text { mol solute } \times \frac{\text { L solution }}{\text { mol solute }}=\text { L solution } \nonumber \]
Combining these two steps into one yields:
\[\text { g solute } \times \left(\dfrac{\text { mol solute }}{\text { g solute }}\right) \times \left( \dfrac{\text { L solution }}{\text { mol solute }} \right) =\text { L solution } \nonumber \]
\[75.6\, \text{g}\, \ce{CH3CO2H} \left(\frac{\text{mol}\,\ce{CH3CO2H}}{60.05\,\text{g} }\right)\left(\dfrac{\text{ L solution }}{0.839\, \text{mol}\,\ce{CH 3CO2H} }\right)=1.50\, \text{L} \text { solution } \nonumber \]
Exercise \(\PageIndex{5}\)
What volume of a 1.50- M KBr solution contains 66.0 g \(\ce{KBr}\)?
- Answer
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0.370 L
Dilution of Solutions
Dilution is the process whereby the concentration of a solution is lessened by the addition of solvent. For example, a glass of iced tea becomes increasingly diluted as the ice melts. The water from the melting ice increases the volume of the solvent (water) and the overall volume of the solution (iced tea), thereby reducing the relative concentrations of the solutes that give the beverage its taste (Figure \(\PageIndex{3}\)).
Dilution is also a common means of preparing solutions of a desired concentration. By adding solvent to a measured portion of a more concentrated stock solution , a solution of lesser concentration may be prepared. For example, commercial pesticides are typically sold as solutions in which the active ingredients are far more concentrated than is appropriate for their application. Before they can be used on crops, the pesticides must be diluted. This is also a very common practice for the preparation of a number of common laboratory reagents.
A simple mathematical relationship can be used to relate the volumes and concentrations of a solution before and after the dilution process. According to the definition of molarity, the number of moles of solute in a solution ( n ) is equal to the product of the solution’s molarity ( M ) and its volume in liters ( L ):
\[n=M L \nonumber \]
Expressions like these may be written for a solution before and after it is diluted:
\[\begin{aligned}
n_1 &=M_1 L_1\\[4pt]
n_2 &=M_2 L_2
\end{aligned} \nonumber \]
where the subscripts “1” and “2” refer to the solution before and after the dilution, respectively. Since the dilution process does not change the amount of solute in the solution, n 1 = n 2 . Thus, these two equations may be set equal to one another:
\[M_1 L_1=M_2 L_2 \nonumber \]
This relation is commonly referred to as the dilution equation. Although this equation uses molarity as the unit of concentration and liters as the unit of volume, other units of concentration and volume may be used as long as the units properly cancel per the factor-label method. Reflecting this versatility, the dilution equation is often written in the more general form:
\[C_1 V_1=C_2 V_2 \nonumber \]
where \( C\) and \( V\) are concentration and volume, respectively.
Link to Learning
Use the simulation to explore the relations between solute amount, solution volume, and concentration and to confirm the dilution equation.
Example \(\PageIndex{6}\): Determining the Concentration of a Diluted Solution
If 0.850 L of a 5.00- M solution of copper nitrate, Cu(NO 3 ) 2 , is diluted to a volume of 1.80 L by the addition of water, what is the molarity of the diluted solution?
Solution
The stock concentration, C 1 , and volume, V 1 , are provided as well as the volume of the diluted solution, V 2 . Rearrange the dilution equation to isolate the unknown property, the concentration of the diluted solution, C 2 :
\[\begin{align*}
C_1 V_1 &=C_2 V_2\\[4pt]
C_2 &=\frac{C_1 V_1}{V_2}
\end{align*} \nonumber \]
Since the stock solution is being diluted by more than two-fold (volume is increased from 0.85 L to 1.80 L), the diluted solution’s concentration is expected to be less than one-half 5 M . This ballpark estimate will be compared to the calculated result to check for any gross errors in computation (for example, such as an improper substitution of the given quantities). Substituting the given values for the terms on the right side of this equation yields:
\[C_2=\dfrac{0.850 L \times 5.00 \frac{ mol }{ L }}{1.80 L }=2.36 M \nonumber \]
This result compares well to our ballpark estimate (it’s a bit less than one-half the stock concentration, 5 M ).
Exercise \(\PageIndex{6}\)
What is the concentration of the solution that results from diluting 25.0 mL of a 2.04- M solution of CH 3 OH to 500.0 mL?
- Answer
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0.102 M CH 3 OH
Example \(\PageIndex{7}\): Volume of a Diluted Solution
What volume of 0.12 M HBr can be prepared from 11 mL (0.011 L) of 0.45 M HBr?
Solution
Provided are the volume and concentration of a stock solution, V 1 and C 1 , and the concentration of the resultant diluted solution, C 2 . Find the volume of the diluted solution, V 2 by rearranging the dilution equation to isolate V 2 :
\[\begin{align*}
C_1 V_1 &=C_2 V_2\\[4pt]
V_2 &=\dfrac{C_1 V_1}{C_2}
\end{align*} \nonumber \]
Since the diluted concentration (0.12 M ) is slightly more than one-fourth the original concentration (0.45 M ), the volume of the diluted solution is expected to be roughly four times the original volume, or around 44 mL. Substituting the given values and solving for the unknown volume yields:
\[\begin{align*}
V_2&=\dfrac{(0.45\,\text{M})(0.011 \,\text{L})}{(0.12\, \text{M})} \\[4pt]
&=0.041 L
\end{align*} \nonumber \]
The volume of the 0.12- M solution is 0.041 L (41 mL). The result is reasonable and compares well with the rough estimate.
Exercise \(\PageIndex{7}\)
A laboratory experiment calls for 0.125 M HNO 3 . What volume of 0.125 M HNO 3 can be prepared from 0.250 L of 1.88 M HNO 3 ?
- Answer
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3.76 L
Example \(\PageIndex{8}\): Volume of a Concentrated Solution Needed for Dilution
What volume of 1.59 M KOH is required to prepare 5.00 L of 0.100 M KOH?
Solution
Given are the concentration of a stock solution, C 1 , and the volume and concentration of the resultant diluted solution, V 2 and C 2 . Find the volume of the stock solution, V 1 by rearranging the dilution equation to isolate V 1 :
\[\begin{align*}
C_1 V_1 &=C_2 V_2\\[4pt]
V_1 &=\dfrac{C_2 V_2}{C_1}
\end{align*} \nonumber \]
Since the concentration of the diluted solution 0.100 M is roughly one-sixteenth that of the stock solution (1.59 M ), the volume of the stock solution is expected to be about one-sixteenth that of the diluted solution, or around 0.3 liters. Substituting the given values and solving for the unknown volume yields:
\[\begin{align*}
V_1&=\frac{(0.100\,\text{M})(5.00\,\text{L})}{1.59\,\text{M}} \\[4pt]
&=0.314\,\text{L}
\end{align*} \nonumber \]
Thus, 0.314 L of the 1.59- M solution is needed to prepare the desired solution. This result is consistent with the rough estimate.
Exercise \(\PageIndex{8}\)
What volume of a 0.575- M solution of glucose (\(\ce{C6H12O6}\)) can be prepared from 50.00 mL of a 3.00- M glucose solution?
- Answer
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0.261 L