4. The Kidneys

Question 1

Main function of kidneys?

Answer 1

Filter waste products out of blood and reabsorb useful solutes.
Regulate water content

Question 2

Ultrafiltration?

Answer 2

Filtering of blood that takes place under pressure, as blood passes from glomerulus into bowmans capsule.

Question 3

Selective reabsorption?

Answer 3

Reabsorbtion of useful substances along the kidney nephron back into blood

Question 4

What is a nephron ?

Answer 4

One of the filtering units of kidney.

Responsible for removing waste products from blood and involved in regulating water potential of blood.

Question 5

Where does ultrafiltration occur?

Answer 5

In the glomerulus and bowmans capsule:

Question 6

Where does blood from renal artery go ?

Answer 6

Into smaller arterioles in the cortex of kidney.

Question 7

What does each arteriole split into ?

Answer 7

Glomerulus which is a bundle of capillaries looped inside hollow ball called bowmans capsule.

Question 8

What is the arteriole that takes blood into glomerulus ?

Answer 8

Afferent arteriole.

Question 9

What is the arteriole that takes filtered blood away from glomerulus?

Answer 9

Efferent arteriole.

Question 10

Different between efferent and afferent?

Answer 10

Efferent smaller in diameter than afferent.

So blood under high pressure at efferent.

Question 11

What does the high pressure do at the efferent arteriole ?

Answer 11

Forces liquid and small molecules in blood out of capillary into bowmans capsule.

Question 12

Where do the liquid and small molecules go ?

Answer 12

Through 3 layers to get to bowmans capsule

capillary endothelium.
Basement membrane.
Epithelium of bowmans capsule.

Question 13

What are the cells called that make up epithelium of bowmans capsule?

Answer 13

Podocytes.

Question 14

What are the substances called that enter bowmans capsule ?

Answer 14

glomerular filtrate.

It Passes through rest of nephron and useful substances are reabsorbed along the way.

Question 15

Where does the glomerular filtrate eventually go ?

Answer 15

Through collective duct and passes out of kidney along ureter.

Question 16

What can the glomerular filtrate also be called?

Answer 16

Tubular fluid.

Question 17

Where does selective reabsoprtion occur?

Answer 17

Along the proximal convoluted tubule
Loop of Henle
Distal convoluted tube.
as the glomerular filtrate passes by

Question 18

Where do useful substances end up going ?

Answer 18

To capillary network wrapped around them from the tubules.

Question 19

Which 2 things are found in medulla?

Answer 19

Loop of Henle.

Ureter.

Question 20

What 5 things found in cortex?

Answer 20

Renal artery.
Bowmans capsule.
PCT
DCT
Collecting duct

Question 21

What is present on the epithelium of the wall on the PCT?

Answer 21

Microvili

Question 22

What do the microvilli do ?

Answer 22

Increase surface area for reabsorbtion of useful substances from glomerular filtrate.

Question 23

Name some useful substances which are reabsorbed ?

Answer 23

Glucose.

Along pct by facilitated diffusion

Question 24

How does water enter blood ?

Answer 24

Osmosis.

As water potential of blood is lower than that of the filtrate.

Question 25

Where is water reabsorbed from ?

Answer 25

Pct
Loop of Henle
DCT
Collecting duct

Question 26

What is urine made up of ?

Answer 26

Water 
Dissolved salts
Urea 
Hormones 
Excess vitamins

Question 27

What does urine NOT contain?

Answer 27

Proteins
Blood cells as they’re too big to be filtered out of blood.
Glucose - actively reabsorbed into blood.

Question 28

What is urea?

Answer 28

Product produced from breakdown of amino acids in liver.