13.14 Homeostasis

Question 1

Homeostasis definition

Answer 1

The maintenance of a stable internal environment within narrow limits

Question 2

Negative feedback definition

Answer 2

When there is an increase/decrease from the norm, the opposite effect is instigated

Question 3

Positive feedback definition

Answer 3

When a deviation from an optimum causes an even greater deviation from the normal

Question 4

3 examples of negative feedback

Answer 4

Body temperature
pH

Question 5

Positive feedback example

Answer 5

Contractions before childbirth

Question 6

What happens when the body temperature is too low?

Answer 6

Metabolic reactions take place too slow
Less kinetic energy
Less frequent successful collisions
Less ESC formed

Question 7

What happens if the body temperature is too high?

Answer 7

Enzymes become denatures
Breaks hydrogen and ionic bonds
Changes the 3 structure

Question 8

What happens if blood pH deviates from the norm?

Answer 8

Enzymes and other proteins become denatures
IE - haemoglobin, plasma proteins, antibodies and membrane proteins

Question 9

Endotherms definition

Answer 9

Maintain their body temperature through behavioural and physiological means

Question 10

Endotherms example

Answer 10

Mammals, birds and some fish

Question 11

Ectotherms definition

Answer 11

Maintain their body temperature by behavioural means only

Question 12

Ectotherms example

Answer 12

Reptiles
Amphibians
Most fish
Invertebrates