excretion

Question 1

3 main kidney roles

Answer 1

-remove urea from blood
-maintain ion levels
-maintain water content

Question 2

where is urea produced?

Answer 2

-in liver from excess amino acids

Question 3

what are the nephrons?

Answer 3

-the filtration unit in kidneys

Question 4

ultrafiltration process…

Answer 4

-blood from renal artery flows through glomerulus
-high pressure built up
-squeezes (water, urea, ions and glucose) out of blood to Bowmans capsule
-big molecules stay in blood
-filtered liquid is known as glomerular filtrate

Question 5

reabsorption process…

Answer 5

-all glucose reabsorbed from proximal convoluted tubule
-sufficient ions reabsorbed
-sufficient water reabsorbed from collection duct

Question 6

how is water lost?

Answer 6

-sweating
-breathing
-weeing

Question 7

what is osmoregulation?

Answer 7

-balance of water coming in and out

Question 8

what does ADH help?

Answer 8

-to control water content
-by making collecting ducts more permeable so more water can be reabsorbed

Question 9

what does the brain do in terms of water content?

Answer 9

-monitors water content
-instructs pituitary gland to release ADH according to how much is needed

Question 10

what happens when there’s too much water?

Answer 10

-brain detects water gain
-pituitary gland releases less ADH
-kidney reabsorbs less

Question 11

what happens when there’s too little water?

Answer 11

-brain detects water loss
-pituitary gland releases more ADH
-kidney reabsorbs more