Lecture 1

Question 1

The August Krough Principle

Answer 1

For a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied

Question 2

Homeostasis

Answer 2

• the tendency for animals to maintain relativr internal stability in the face of external fluctuations
• maintained by regulatory systems
• homeostasis does not equal constancy

Question 3

Negative Feedback

Answer 3

• control systems regulate a variable by opposing its deviation from a set-point, thereby keeping the variable within its homeostasis range
• Ex. Regulation of blood glucose

Question 4

Positive Feedback

Answer 4

• Control systems regulates non-homeostatic change and create rapid change away from a set-point. This promotes a large, unidirectional response
• Ex. The regulation of birth (paturition) in mammals

Question 5

Changing the Set Point:
1. Acclimation

Answer 5

Process of change in response to a controlled environment variable in the lab

Question 6

Changing the Set Point:
2. Acclimatization

Answer 6

Process of change in response to a natural environmental variation

Question 7

Changing the Set Point:
3. Adaptation

Answer 7

Process of change through natural selection leading to an organism whose physiology, anatomy, and behavior are matched to the demands of its environment