After his third helping of apple pie and ice cream, Nathan feels quite full. His satiation is due, at least in part, to increased levels of the:
A)hormone epinephrine.
B)hormone ghrelin.
C)hormone cholecystokinin (CCK).
D)neurotransmitter neuropeptide Y (NPY).

Question

Quizplus · Accepted Answer

Hormone cholecystokinin (CCK) is released from the small intestine in response to the presence of fat or protein, which slows down gastric emptying and creates a feeling of fullness. This feeling of fullness is what causes satiation.

Answer: D
 Neurotransmitter neuropeptide Y (NPY) is released in the hypothalamus in response to hunger signals and promotes eating behavior. However, its levels drop after eating, contributing to satiation. So, it can also be a part of the increased satiation Nathan is feeling after his third helping of apple pie and ice cream.

A) and B) are less likely to contribute to satiation in this scenario. Hormone epinephrine is typically released during the fight-or-flight response, whereas hormone ghrelin is known as the hunger hormone and stimulates appetite.

After His Third Helping of Apple Pie and Ice Cream