Metabolism and adverse conditions

Question 1

Which abiotic factors can affect an organisms metabolic rate?

Answer 1

Temperature, salinity, pH

Question 2

What is a conformer?

Answer 2

An organism which cannot maintain its metabolic rate through physiological mechanisms.

Question 3

What is a conformers internal environment dependent on?

Answer 3

Its external environment.

Question 4

What is an advantage of being a conformer?

Answer 4

Low metabolic costs

Question 5

What are the disadvantages of being a conformer?

Answer 5

Narrow range of ecological niches, cannot tolerate dramatic changes to environment.

Question 6

What is a regulator?

Answer 6

An organism which can maintain a steady internal environment by using physiological mechanisms.

Question 7

What is an advantage of being a regulator?

Answer 7

Can occupy a wide range of ecological niches.

Question 8

What is a disadvantage of being a regulator?

Answer 8

Requires energy to maintain homeostasis.

Question 9

What is homeostasis?

Answer 9

Maintaining steady conditions within an organism.

Question 10

What is negative feedback control?

Answer 10

Any change in a condition from the optimum is detected by receptors that switch on a corrective mechanism to restore the conditions to normal. The corrective mechanism is then switched off.

Question 11

What is a receptor?

Answer 11

Cells which detect changes in the environment and send signals to effectors.

Question 12

What is an effector?

Answer 12

Parts of the body that respond to messages send by receptors.

Question 13

Which part of the brain is described as the temperature monitoring centre?

Answer 13

Hypothalamus

Question 14

What are the effectors involved in thermoregulation?

Answer 14

Sweat glands, skin arterioles, hair erector muscles, skeletal muscles.

Question 15

How are signals sent from the hypothalamus to the effectors in thermoregulation?

Answer 15

By nerve impulses

Question 16

What happens in mammals as a response to increased temperature?

Answer 16

Increased sweat production, vasodilation, hairs lowered

Question 17

What happens in mammals as a response to decreased temperature?

Answer 17

Hair erector muscles contract, vasoconstriction, decreased sweat production, shivering

Question 18

How does sweating lead to a decrease in body temperature?

Answer 18

The body evaporates the water from the skin which lowers body temperature by convection.

Question 19

What is vasodilation?

Answer 19

When the skin arterioles widen increasing blood flow to the surface of the skin increasing heat loss by radiation.

Question 20

What is vasoconstriction?

Answer 20

When the skin arterioles narrow reducing blood flow to the surface of the skin and reducing heat loss by radiation.

Question 21

How do hairs on your body standing up increase temperature?

Answer 21

They trap a layer of insulating air reducing heat loss

Question 22

What is an advantage to maintaining a constant body temperature?

Answer 22

To ensure the optimum temperature for enzymes to maintain a high metabolic rate.

Question 23

What is thermoregulation?

Answer 23

Use of negative feedback control to regulate body temperature in mammals

Question 24

Other than enzyme activity why else is temperature important?

Answer 24

It affects diffusion rates, diffusion of oxygen and glucose into cells for respiration is faster in warmer temperatures to maintain high metabolic rates.

Question 25

How can conformers maintain optimum metabolic rates?

Answer 25

Behavioural responses like basking on rocks.