What do the kidney's do? What is homeostasis?

Question 1

homeostasis is..

Answer 1

keeping the internal conditions in the body constant

Question 2

what needs to be kept constant?

Answer 2

concentration of glucose
ions
water
waste products

Question 3

what are the 2 main waste products?

Answer 3

co2 produced by aerobic respiration.. removed by the lungs during breathing
urea produced in liver by breakdown of amino acids, removed from bloodstream by KIDNEYS and leaves the body as urine

Question 4

Kidneys help to adjust ion content

Answer 4

ions such as Na+ enter body when we eat and drink

Question 5

what happens if the level of water and ions are not managed?

Answer 5

water can move into and out of cells by osmosis, damaging the cells

Question 6

we have 2 kidneys how do we remove urea? 4

Answer 6

1) blood enters through artery (away from heart) blood contains urea
2) kidneys filter out blood
3) temporarily stored in the bladder
4) blood leaves the kidney though vein (to heart) blood doesn’t contain urea

Question 7

How do the kidneys remove molecules from the blood?

Answer 7

1) ULTRAFILTRATION high pressure built squeezes out urea, water and ions and sugar out blood into BOWMANS CAPSULE - BLOOD CELLS PROTEINS NOT FILTERED OUT
2) REABSORPTION useful substances reabsorbed e.g. ALL GLUCOSE, some ions excess not (active transport), some water
3) RELEASE OF WASTE - urea out of nephron to ureter to bladder as urine