Osmoregulation

Question 1

How does the kidney control the water level in the blood beginning with when it has detected too little water

Answer 1

Too little water is detected by the hypothalamus in the brain. This causes the pituitary gland (in the brain) to secrete the hormone ADH. The ADH causes Aquaporins. In the collecting duct to open. This means more water goes back into the blood.

Question 2

When there is too much water in the blood what happens

Answer 2

Too much water in the blood. This is detected by the hypothalamus. This stops the pituitary glands secreting ADH. This causes the Aquaporins to close. This means that less water is reabsorbed into the blood.

Question 3

What is a hormone

Answer 3

A chemical messenger secreted by a gland that sends a message to a target organ

Question 4

What is ADH

Answer 4

Anti diuretic hormone. Secreted by the pituitary gland. It acts on the collecting duct in the kidney. It increases water reabsorption into the blood

Question 5

What are Aquaporins

Answer 5

These are holes in the sides of the collecting duct. They open when ADH is present so more water is reabsorbed into the blood

Question 6

What is negative feedback

Answer 6

A process out in place to counteract or reverse a change from normal

Question 7

What solution do you use to test for sugars

Answer 7

Benedict’s solution

Question 8

What do you use to test for proteins

Answer 8

The biurets test

Question 9

Why does sweating improve the rate of cooling

Answer 9

When you are hot you experience vasodilation (blood goes to the skin surface). By sweating your body produces water onto the skin which then must be evaporated. It takes the thermal heat and converts it into kinetic energy in order to evaporate and therefore takes away some of the heat

Question 10

In what 3 ways can the body lose water

Answer 10

Urine
Breathing
Sweating

Question 11

What do the kidneys do

Answer 11

They control the level of water in the blood