1
Triple only
[1 mark]Which tube carries urine from the kidney to the bladder?
- Urethra
- Renal vein
- Ureter
- Renal artery
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Answer: C C (1)
2
Triple only
[2 marks]State where urea is produced and what it is produced from.
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- in the liver (1)
- from the breakdown of excess amino acids (1)
3
Triple only
[3 marks]Describe how the kidney filters blood in the glomerulus and Bowman's capsule.
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- blood in the glomerulus is at high pressure (1)
- small molecules such as water, glucose, urea and ions are forced into the Bowman's capsule (1)
- large molecules such as proteins and blood cells stay in the blood (1)
4
Triple only
[3 marks]Glucose is filtered at the glomerulus, but the urine of a healthy person contains no glucose. Explain why.
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- all the glucose is reabsorbed (1)
- back into the blood (1)
- by active transport, using energy from respiration (1)
5
Triple onlyHigher tier
[4 marks]On a hot day a person sweats a lot and the water content of the blood falls. Explain how ADH helps to return the water content to normal.
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- more ADH is released (from the pituitary gland) (1)
- ADH makes the collecting duct more permeable to water (1)
- more water is reabsorbed into the blood (1)
- a small volume of concentrated urine is produced (1)
6
Triple only
[3 marks]Describe two treatments for kidney failure.
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- dialysis: blood passes through a machine, separated from dialysis fluid by a partially permeable membrane (1)
- urea (and excess ions) pass out of the blood into the dialysis fluid (1)
- transplant: a healthy kidney from a donor is put into the patient (1)
- the donor kidney must be a good tissue match / the patient takes drugs to stop the immune system rejecting it (1)
- Max 3