Key Area 2.4 Conformers and regulators

Question 1

What is an abiotic factor?

Answer 1

A factor in an organisms external environment which can affect their metabolic rate.

Question 2

What are some examples of abiotic factors?

Answer 2

Temperature
pH
Salinity.

Question 3

What is a conformer?

Answer 3

The state of a conformers internal environment is dependant on the abiotic factors in its external environment.

Question 4

What is an example of a conformer?

Answer 4

Snakes.

Question 5

What is a regulator?

Answer 5

The internal environment of a regulator is not dependant on the external environment.

Question 6

What is an example of a regulator?

Answer 6

Humans.

Question 7

What kind of ecological niche do conformers have?

Answer 7

A narrow one.

Question 8

What kind of ecological niche do regulators have?

Answer 8

A wide one.

Question 9

What is a disadvantage of being a regulator compared to a conformer?

Answer 9

Regulators have much higher metabolic costs than conformers.

Question 10

What is a way that conformers use to maintain their optimum metabolic rate?

Answer 10

Behavioural responses.

Question 11

What is homeostasis?

Answer 11

The maintenance if the bodys internal environment within limits despite the external environment.

Question 12

What is negative feedback control?

Answer 12

When a body internal environment deviates from normal it is detected by receptors and these receptors send hormonal or nervous impulses and effectors act to return the internal environment back to normal.

Question 13

What is the temperature monitoring centre in humans called?

Answer 13

The hypothalamus.

Question 14

What does the hypothalamus contain?

Answer 14

Thermoreceptors.

Question 15

What does the hypothalamus receive?

Answer 15

Nerve impulses from the skin.

Question 16

What does the body do when to is too cold?

Answer 16

Shivering: muscles relax and contract continuously to generate heat from movement.
Vasoconstriction: Blood vessels become narrower to reduce heat loss from radiation. Blood is diverted to internal organs.
Hair erector muscles contract: This traps a layer of insulating air.
Decreased sweat production: Prevents heat loss through evaporation.

Question 17

What does the body do when it is too hot?

Answer 17

Increased sweat production: The evaporation of water of the skin has a cooling effect.
Vasodilation: Blood vessels become wider to allow more heat loss through the skin by radiation.
Hair erector muscles relax: Loss of layer of insulating air.

Question 18

What are some advantages of maintaining a constant body temperature?

Answer 18

Allows animals to maintain the optimum temperature for enzyme activity.
Allows high diffusion rates.