The Kidney

Question 1

Name the structure that delivers blood INTO the kidney?

Answer 1

The renal artery

Question 2

Name the structure that delivers blood OUT OF the kidney

Answer 2

The renal vein

Question 3

Blood from the renal artery enters _____________

Answer 3

Blood from the renal artery enters _ smaller arterioles in the cortex of the kidney

Question 4

The _____ ______ takes blood into the glomerulus

Answer 4

The afférent artériole takes blood into the glomerulus

Question 5

What is the glomerulus?

Answer 5

A bundle of capillaries looped inside the Bowman’s capsule

Question 6

Ultrafiltration is also known as?

Answer 6

Glomerular filtration

Question 7

The blood is under high pressure which causes ultrafiltration. Why is the blood under high pressure?

Answer 7

1) Pumped from aorta, high pressure as has to get around whole body
2) The afférent artériole is WIDER than the efferent artériole. This acts like when a lane is closed on the motorway.

Question 8

State the three layers in glomerular filtration

Answer 8

1) Capillary fenestrations
2) Basement membrane
3) Bowman’s capsule epithelium (containing podocytes)

Question 9

Describe capillary fenestrations in ultrafiltration

Answer 9

They contain large gaps which allow blood plasma through but not large objects like proteins and erythrocytes (red blood cells) through

Question 10

Describe the basement membrane in ultrafiltration

Answer 10

It supports the cells of the capillary endothelium; acting as a fine filter allowing small plasma proteins through.
(The maximum size that can pass through is called the renal threshold and is a molecular mass of 68,000)

Question 11

Describe the Bowman’s capsule epithelium (and podocytes) in ultrafiltration

Answer 11

The form the lining of the renal capsule and have large gaps between them which allow the glomerular filtrate through into the renal space

Question 12

The outer section of the kidney is called?

Answer 12

The cortex

Question 13

The inner section of the kidney is called?

Answer 13

The medulla

Question 14

Selective réabsorption occurs along the…

Answer 14

PCT
Loop of Henle
DCT

Question 15

PCT =

Answer 15

Proximal convoluted tubule

Question 16

DCT =

Answer 16

Distal convoluted tubule

Question 17

State two adaptations of the PCT cells to enable selective reabsorption

Answer 17

1) High numbers of microvilli —> Increases the sa:vol ratio for the reabsorption of useful materials from the glomerular filtrate into the blood
2) High numbers of mitochondria —> More ATP able to be produced to power the active transport of substances

Question 18

Urine usually contains: (3 points)

Answer 18

1) Water & dissolved salts
2) Urea
3) Other substances such as hormones and excess vitamins

Question 19

Urine doesn’t usually contain: (2 points)

Answer 19

1) Proteins and blood cells –> they’re too big to be filtered out of the blood
2) Glucose, as its actively reabsorbed back into the blood

Question 20

The regulation of the blood’s water potential is called…

Answer 20

Osmoregulation

Question 21

When the water potential of the blood is too low…

Answer 21

1) More water is reabsorbed by osmosis into the blood from the nephron tubules
2) Urine is ore concentrated, less water is lost

Question 22

When the water potential of the blood is too high…

Answer 22

1) Less water is reabsorbed by osmosis into the blood from the nephron tubules
2) Urine is less concentrated, more water is lost

Question 23

Blood ADH level _____ when you’re dehydrated

Answer 23

Rises when you’re dehydrated

Question 24

BLood ADH level _____ when you’re hydrated

Answer 24

Lowers when you’re dehydrated

Question 25

Give the steps when your blood ADH level RISES…

The big 10 point question

Answer 25

(Rises… think MORE)

1) Water potential of blood DECREASES
2) Water moves OUT of osmoreceptors via osmosis
3) Cells DECREASE in volume
4) Sends a signal to other cells in the hypothalamus
5) Sends a signal to the posterior pituitary gland
6) MORE ADH released by the posterior pituitary gland
7) MORE vesicles containing water-permeable channels (aquaporins) to fuse with the membrane
8) DCT & collecting duct become MORE permeable to water
9) MORE water reabsorbed by osmosis
10) Small amount of highly-concentrated urine produced

Question 26

Give the steps when your blood ADH level LOWERS…

The big 10 point question

Answer 26

(Lowers… think LESS)

1) Water potential of blood INCREASES
2) Water moves IN of osmoreceptors via osmosis
3) Cells INCREASE in volume
4) Sends a signal to other cells in the hypothalamus
5) Sends a signal to the posterior pituitary gland
6) LESS ADH released by the posterior pituitary gland
7) LESS vesicles containing water-permeable channels (aquaporins) to fuse with the membrane
8) DCT & collecting duct become LESS permeable to water
9) LESS water reabsorbed by osmosis
10) Large amount of dilute urine produced