Temperature

Question 0

When cold

Answer 0

Skin goes pale because blood vessels get narrower (vasoconstriction)to prevent heat leaving through surface.

Hairs stand up to trap heat

Body shivers, more respiration, more energy to heat the body up

Question 1

When hot

Answer 1

Skin goes red because vessels get wider (vasodilation) to release more heat

Hairs lie down
Sweat to cool skin surface, heat is evaporated

Question 2

Where is the temperature sensed?

Answer 2

In the thermoregulatory centre in the hypothalamus

Blood passes through, receptors sense. Also receptors in skin.