Controlling blood water potential

Question 1

The kidney regulates the ———–of —————

Answer 1

Kidney regulates water potential of blood

Question 2

Why is water essential

Answer 2

To keep body functioning therefore amount of water(water potential)needs to be constant

Question 3

what’s Osmoregulation

Answer 3

Mammals excrete urea (and other waste products) in solution, which means water is lost during excretion.
Water is also lost in sweat. The kidneys regulate the water potential of the blood (and urine),
so the body has just the right amount of water

Question 4

What happens when water potential of the blood is too low

Answer 4

If the water potential of the blood is too low(dehydrated) more water is reabsorbed by osmosis into the blood from the tubules of the nephrons.

Question 5

What happens to urine when water potential in the blood is to low

Answer 5

urine is more concentrated, so less water is lost during excretion.

Question 6

What happens if water potential in the blood is to high

Answer 6

If the water potential of the blood is too high( hydrated) less water is
reabsorbed by osmosis into the blood from the tubules of the nephrons.

Question 7

What happens to urine when water potential is to high

Answer 7

urine is more dilute, so more water is lost during excretion

Question 8

Where does the regulation of water potential take place

Answer 8

regulation potential mainly takes place in the loop of Henle, DCT and collecting duct

Question 9

The volume of

by the DCT and collecting duct is controlled by ————-

Answer 9

hormones

Question 10

The loop of Henle maintains a ———– —– ——–

Answer 10

The Loop of Henle Maintains a Sodium Ion Gradient

Question 11

where is the loop of Henle located

Answer 11

The loop of Henle is located in the medulla (inner layer) of the kidneys

Question 12

What is the loop of Helen made up of

Answer 12

two limbs

the descending limb and the ascending limb.

Question 13

What do the limbs do

Answer 13

The limbs control

the movement of sodium ions so that water can be reabsorbed by the blood.

Question 14

Describe how the loop of Helen maintains a sodium gradient

Answer 14

1. At the top of the ascending limb, Na+ ions are actively transported into the medulla
2. The water potential of the medulla is lowered
3. Water moves out of the descending limb, into the medulla by osmosis
4. The glomerular filtrate is more concentrated
5. At the bottom of the ascending limb, Na+ ions diffuse into the medulla
6. The water potential in the medulla is lowered

Question 15

How is the volume of water reabsorbed into the capillaries

Answer 15

By changing the permeability of the DCT and the collecting duct

Question 16

Water reabsorption is controlled by ————

Answer 16

Hormones

Question 17

what is water potential monitored by and location

Answer 17

cells called osmoreceptors in a part of the brain called the hypothalamus.

Question 18

What happens when water potential in the blood decreases

Answer 18

1. Osmoreceptors in the hypothalamus detect the decrease in water potential
2. Posterior pituitary gland releases ADH
3. ADH binds to receptors on cell membranes of DCT and collecting duct cells
4. Aquaporins move to and fuse with cell membrane
5. More water can pass out and into the medulla so more water is reabsorbed

Question 19

——— ——- levels rises when your dehydrated

Answer 19

Blood ADH

Question 20

Describe how water content in the blood needs to be increased

Answer 20

1) The water content of the blood drops, so its water potential drops.
2) This is detected by osmoreceptors in the hypothalamus.
3) The posterior pituitary gland is stimulated to release more ADH into the blood.
4) More ADH means that the DCT and collecting duct become more permeable,
so more water is reabsorbed into the blood by osmosis.
5) A small amount of highly concentrated urine is produced and less water is lost.

Question 21

Describe the process of water content being reduced

Answer 21

1)The water content of the blood rises, so its water potential rises.
2) This is detected by the osmoreceptors in the hypothalamus.
3) The posterior pituitary gland releases less ADH into the blood.
4) Less ADH means that the DCT and collecting duct become less permeable,
so less water is reabsorbed into the blood by osmosis.
5) A large amount of dilute urine is produced and more water is lost.