Answer to Question 1
During starvation, the body's priority is to supply the nervous system and red blood cells with sufficient glucose. Once glycogen stores have been depleted within the first 24-36 hours of no food intake, glucose must be synthesized from noncarbohydrate substances via gluconeogenesis. Muscles contribute to gluconeogenesis by supplying amino acids, lactate, and glycerol, all of which are used by the liver to generate small amounts of glucose. The loss of lean tissue during the early stages of acute starvation reduces the body's total energy requirements. The body goes into survival mode by dramatically reducing its metabolically active lean tissue. This defensive action is important because it helps prolong survival if starvation continues. In this way, less energy is needed to maintain lean body mass, thus decreasing the body's overall energy needs. Similarly, self-imposed energy restriction, as with some eating disorders and very low-calorie diets, also sacrifices lean tissue to support gluconeogenesis. Successful weight-loss diets advocate slow and gradual weight loss to minimize the loss of lean tissue and thus muscle mass and strength.
Answer to Question 2
c
Osteoporosis. (a) A section through normal spongy bone. (b) A section through a bone with osteoporos
Dominance relationships among individuals play an important role in many primate societies.
Measuring the Weight and Length of an Infant
Overhead stretch for the shoulder muscles. Lean back to create the stretch using your body weight.
Mixed dishes such as hamburgers and pizza are a major source of solid fats in the diets of Americans
Measuring the client’s weight with a standard platform scale