Skip to content
InkFlaskCambridge IGCSE

Pupil sheet · Homeostasis

Homeostasis — final check

Name ______________________ Date ____________

Work alone, with the lesson closed. Answer every question; there are no hints.

1. describe

A person walks from a warm room into a cold porch. After 10 minutes the skin temperature has fallen by 8.5 °C and the core temperature by 0.1 °C. Describe homeostasis, and use these results to explain what it means.

2. compare

Supplement: compare what the arterioles supplying the skin surface capillaries do in a cold porch and in a warm room, and the effect on heat loss.

In the cold porch

In the warm room

3. identify

Supplement: in the diagram of the skin, name the parts labelled Q, T, U and V.

A section through human skin, drawn the other way round, with seven parts lettered P to V: P the vessels carrying blood to and from the surface, Q a small muscle joined to the hair, R the layer of rounded cells under the skin, S a nerve ending just under the surface, T a hair above the surface, U a coiled tube deep in the skin with a duct to the surface, V the nerve fibre leading from S.

Q

T

U

V

4. explain

Supplement: explain how negative feedback keeps the core temperature close to 37 °C when a person walks into a cold porch. Include the role of the brain.

5. describe

After a meal the blood glucose concentration rises, then returns to normal. (a) Identify the hormone that brings it back down, and the organ that secretes it. (b) Supplement: describe what the liver does to return the concentration to normal.

(a) Hormone and organ

(b) What the liver does

6. explain

Supplement: (a) Explain how the blood glucose concentration is raised when it falls during exercise. (b) Outline how Type 1 diabetes is treated.

(a) Raising blood glucose

(b) Treating Type 1 diabetes