Question

If a person did not eat for several days, which sequence of events would occur?
Responses

Glycogen stores would be depleted first, then structural proteins, and then stored lipids.
Glycogen stores would be depleted first, then structural proteins, and then stored lipids.

Glycogen stores would be depleted first, then stored lipids, and then structural proteins.
Glycogen stores would be depleted first, then stored lipids, and then structural proteins.

Lipid stores would be depleted first, then stored glycogen, and then structural proteins.
Lipid stores would be depleted first, then stored glycogen, and then structural proteins.

Proteins stores would be depleted first, then stored lipids, and then stored glycogen.

Answer 1

Glycogen stores would be depleted first, then stored lipids, and then structural proteins.

Explanation: Liver glycogen is used up within ~24 hours of fasting. After glycogen is gone, the body relies mainly on adipose triglycerides (lipolysis and ketone production) for energy. Only with prolonged fasting, when fat reserves become insufficient, does increased breakdown of structural proteins provide substrates for gluconeogenesis.