Chapter 11: Part 5 What Stops a Meal

Question 1

Gastric Factors:

Answer 1

the stomach has receptors that detect the presence of nutrients. We eat what we need.

Question 2

Intestinal Factors:

Answer 2

the intestines also contain nutrient receptors. Some of the chemoreceptors found in the duodenum also found in the tongue and the axons may transmit a satiety signal to the brain. The stomach’s emptying is controlled by a peptide hormone called cholecystokinin or CCK. CCK is released in response to the presence of fats.

Question 3

Liver Factors:

Answer 3

the last stage of satiety appears to occur in the liver. When the liver receives nutrients from the intestines, it sends a signal to the brain that produces satiety.

Question 4

what is an additional satiety signal?

Answer 4

peptide YY

Question 5

Insulin:

Answer 5

insulin permits organs other than the brain to metabolize glucose and then this promotes the nutrients to enter the fat cells where they are then converted into triglycerides. Insulin receptors detect insulin when it is present in the blood, which then tells the brain that the body is in the absorptive phase of metabolism and so it is also involved with satiety.

Question 6

what is leptin?

Answer 6

A hormone secreted by adipose tissue; decreases food intake and increases metabolic rate, primarily by inhibiting NPY-secreting neurons in the arcuate nucleus.