What is the most dramatic metabolic change that occurs with fasting and starvation?
A) catabolism of muscle proteins speeds up
B) ketone body production increases as catabolism of fatty acids rises
C) gluconeogenesis takes place in excess
D) glycolysis takes place in excess
E) insulin level increases to metabolize the excess glucose produced

Question

Quizplus · Accepted Answer

The most dramatic metabolic change that occurs with fasting and starvation is the increase in ketone body production as the body shifts to using fatty acids as the primary source of energy. This occurs because glycogen stores are depleted and gluconeogenesis (the production of glucose from non-carbohydrate sources) cannot keep up with the body's energy demands. As a result, the liver produces ketone bodies from fatty acids to be used as an alternative source of energy by the brain and other organs. Catabolism of muscle proteins may occur, but is not the primary metabolic change. Gluconeogenesis occurs to maintain glucose levels, but not in excess, as this would be energetically inefficient. Glycolysis may occur in the absence of sufficient oxygen, but this is not a major metabolic change during fasting and starvation. Insulin levels decrease during fasting and starvation as there is little glucose available for metabolism.

What Is the Most Dramatic Metabolic Change That Occurs with Fasting