Homeostasis and Feedback Control

Practice: Given the following diagram:

Circle One for each of the following: 

1. The connection between A and B is ( sign-preserving / sign-inverting ). 

2. The connection between B and C is ( sign-perserving / sign-inverting ). 

● Changes in negative feedback loops may be written out linearly in arrow form.

Practice: Given the following diagram:

Circle One for each of the following: 

1. The variable with a SET POINT is ( [Glucose]blood / [Insulin]blood ). 

2. The SENSOR is (β cells / [Insulin]blood / Eating Food ).

Practice: Body temperature is another homeostatic variable. So, the occurrence and regulation of a fever is an example of (choose all that apply):

Practice: Identify each of the following as an example of positive feedback, negative feedback, or feed-forward. 

1. ↑GnRH→↑FSH→↑Estrogen→↓GnRH 

2. ↑A→↑B→↑C→↑D 

3. ↓Blood pH→↑Respiratory Rate→↑CO2 release from blood→↑blood pH 

4. Depolarization→↑Inward Na+ current→↑Depolarization