Chapter 13.2:Homeostasis

Question 1

Define homeostasis

Answer 1

the maintenance of a constant internal environment

Question 2

What happens if the level of glucose in the blood is too high

Answer 2

the water potential of the blood becomes very low,the water moves out of cells into the blood by osmosis.this leads to the cells shrinking and eventually dying

Question 3

what happens if the level of glucose is too low

Answer 3

the water potential is high so the water moves from the blood into the cells,causing them to burst.maintaining a constant blood glucose level therefore maintains a constant water potential so no unwanted osmosis occurs.

Question 4

What hormone is released when blood glucose concentration is too high

Answer 4

Insulin

Question 5

Why is insulin released when blood glucose level is too high

Answer 5

Insulin causes glucose to be converted to glycogen in the liver.this lowers the concentration of glucose in cells,so glucose diffuses into cells from the blood,lowering the amount of glucose in the blood.

Question 6

What hormone is realised when blood glucose concentration is low

Answer 6

Glucagon

Question 7

Why is glycogen released when blood glucose concentration is too low.

Answer 7

Glycogen inhibits glucose being converted to glycogen in the liver and activated an enzyme that converts glycogen to glucose,making more glucose available to cells.it also decreases the respiratory rate in cells so that less glucose is used in respiration