Myosin can only bind to actin when the binding sites on actin are exposed by calcium ions. Actin molecules are bound to the Z line, which forms the borders of the sarcomere. Other bands appear when the sarcomere is relaxed. A muscle fiber from a biceps muscle may contain 100,000 sarcomeres.uscle fibers are composed of tubular myofibrils. Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands. Sarcomeres are composed of long, fibrous proteins as filaments that slide past each other when a muscle contracts or relaxes.
What causes bulimia? Bulimia is more than just a problem with food. A binge can be triggered by dieting, stress, or uncomfortable emotions, such as anger or sadness. Purging and other actions to prevent weight gain are ways for people with bulimia to feel more in control of their lives and ease stress and anxiety.
How Alcohol Affects the Body. Even a small amount of alcohol has an affect on your body. When you drink, alcohol is absorbed into your bloodstream and distributed throughout your body. A tiny amount of alcohol exits your body in your urine and your breath.You absorb alcohol more slowly if you eat, especially if the food is high in fat.However, if you drink more than your body can process, youâll get drunk. How quickly alcohol is metabolized depends on your size and gender, among other things. tiny amount of alcohol exits your body in your urine and your breath. You absorb alcohol more slowly if you eat, especially if the food is high in fat. However, if you drink more than your body can process, youâll get drunk. How quickly alcohol is metabolized depends on your size and gender, among other things.