The kidney

Question 1

What is the function of the excretory system?

Answer 1

removes urea which is a waste product of the metabolism and regulates the water content of the blood.

Question 2

Label the parts of the body that are involved in the excretory system

Answer 2

• Diaphragm
• Kidney
• Renal artery
• Renal vein
• Ureter
• Bladder
• Muscle
• Urethra

Question 3

How does the excretory system clean the blood?

Answer 3

• blood from the aorta moves into the renal artery and into the kidney
• the kidney filters the blood and removes some water, urea and excess salts
• the clean blood returns to the heart via the vena cava
• the filtrate called urine leaves the kidneys in the ureters and is then stored in the bladder
• urine is passed out of the body through the urethra

Question 4

How does the kidney detect diseases?

Answer 4

• red blood cells in the urine can indicate kidney damage or disease
• glucose in the urine can indicate diabetes

Question 5

Efferent arteriole

Answer 5

narrower than the afferent, creating pressure in the glomerulas

Question 6

Afferent arteriole

Answer 6

brings blood to the nephron

Question 7

Proximal convoluted tubule

Answer 7

this is where selective reabsorption begins

Question 8

Bowman’s capsule/ glomerulus

Answer 8

This is where filtration occurs under high pressure and it is where glucose, urea, salts and water are forced out of the blood and into the capsule

Question 9

Peritubular capillaries

Answer 9

They are supplied by the efferent arteriole and they run alongside the nephron and allow reabsorption `

Question 10

Descending loop of Henle

Answer 10

it is where osmoregulation occurs because it is where the body reabsorbs water

Question 11

Ascending loop of Henle

Answer 11

reabsorbs sodium and chlorine

Question 12

Distal tubule

Answer 12

where selective reabsorption occurs, whatever is left such as glucose will be reabsorbed

Question 13

Collecting duct

Answer 13

responds to ADH, if there is an increase in ADH more water is reabsorbed, if there is a decrease in ADH less water is reabsorbed

Question 14

How does the body control the level of water in the blood if the water levels are too low?

Answer 14

• osmoreceptors in the brain detect the water content of the blood is too low
• more ADH is released into the blood from the posterior lobe of the pituitary gland
• blood takes more ADH to the distal convoluted tubule and collecting duct of the kidney
• the distal convoluted tubule and collecting duct become more permeable to water
• water in the collecting duct is reabsorbed into the surrounding tissue fluid by osmosis
• a small volume of concentrated urine is released

Question 15

How does the body control the level of water in the blood is the water levels are too high?

Answer 15

• osmoreceptors in the brain detect the water content of the blood is too high
• less ADH is released into the blood from the posterior lobe of the pituitary gland
• blood takes less ADH to the distal convoluted tubule and collecting duct of the kidney
• the distal convoluted tubule and collecting duct becomes less permeable to water
• water is retained in the collecting duct
• a large volume of dilute urine is released