Question

Because there can be a long delay between ingestion and the digestion/assimilation of a substance into a system, a ________ is needed to help regulate ingestive behavior.

1) satiety mechanism
2) set point
3) positive feedback loop
4) negative feedback factor
5) correctional mechanism

Answer 1

A satiety mechanism involving a negative feedback loop regulates ingestive behavior by sending signals of fullness, leading to the cessation of eating.

Step-by-step explanation:

Because there can be a long delay between ingestion and the digestion/assimilation of a substance into a system, a satiety mechanism is needed to help regulate ingestive behavior. The satiety mechanism involves a number of physiological responses that signal when to stop eating.


As food is consumed, blood glucose levels rise, which leads to the release of hormones that bring a sense of fullness and satisfaction, effectively stopping further eating behavior. This is an example of a negative feedback loop, where the stimulus for eating changes direction in response to signals indicating satiety; for instance, as fat cells release the satiety hormone leptin.

State whether each of the following processes is regulated by a positive or negative feedback loop:

• a. A person feels satiated after eating a large meal - Negative feedback loop
  
• b. The blood has plenty of red blood cells. As a result, erythropoietin, a hormone that stimulates the production of
  new red blood cells, is no longer released from the kidney - Negative feedback loop