Thermoregulation

Question 1

What is thermoregulation?

Answer 1

The process that the body uses to keep its internal temperature steady.

Question 2

What is the optimum temperature for enzymes in the human body?

Answer 2

37°C

Question 3

What happens to enzymes if the human body temperature isn’t maintained?

Answer 3

Enzyme activity slows down, enzymes can denature and stop working above or below this temperature

Question 4

Where is the thermoregulatory system?

Answer 4

In the hypothalamus

Question 5

How can the hypothalamus control body temperature?

Answer 5

• Contains receptors that are sensitive to blood temperature in the brain
• Receives impulses from nerve endings in skin (provide info about external temperature)

Question 6

What happens when you are too hot?

Answer 6

1) Erector muscles RELAX + hairs lie flat
2) Lots of sweat is produced in the sweat glands in the dermis. The sweat is released through pores in the epidermis. The sweat EVAPORATES, TRANSFERRING ENERGY FROM YOU TO THE SURROUNDINGS.
3) Blood vessels close to the surface dilate. Allows more blood to flow to the surface so it can transfer more energy to the surroundings (VASODILATION)

Question 7

What is vasodilation?

Answer 7

Blood vessels close to the surface of the skin DILATE

More blood flows near surface of skin - more energy can be transferred to surroundings

Question 8

What happens when you are too cold?

Answer 8

1) Erector muscles CONTRACT - hairs stand on end, trapping an insulating layer or air near the skin’s surface (keeps you warm)
2) little sweat is produced
3) VASOCONSTRICTION- blood vessels near surface of skin contract, so less energy is transferred to surroundings
4) SHIVER - muscles contract automatically, increases the rate of respiration, transfers more energy to warm body.