Zoo 251: Chapter 26- body weight and energy balance & appetite
Zoo 251: Chapter 26- body weight and energy balance & appetite
weight is determined by one's energy balance- if energy intake and output are equal, body weight is stable
if intake exceeds output - weight gain
output exceeds intake - weight loss
SHORT-TERM REGULATORS OR APPETITE:
Ghrelin- secreted by parietal cells in the gastric fundus, esp. when stomach empty
produces sensation of hunger and stimulates the hypothalamus to secrete growth hormone-releasing hormone, priming the body to take advantage of the nutrients about to be absorbed
within an hour after eating, ghrelin secretion ceases
Peptide YY (PYY)- secreted by enteroendocrinecells in the ileum and colon, which sense that food has arrived even as it enters the stomach