urinary

Question 1

bladder holds

Answer 1

700-800mL
stretch receptors usually signal to pee at 200-400mL

Question 2

bladder muscle

Answer 2

detruser muscle w/ 2rd longitudinal muscle

Question 3

bladder mucosa is

Answer 3

transitional epithelium

Question 4

how many nephrons

Answer 4

25M nephrons in each kidney

Question 5

how much kidney filter per day

Answer 5

180L

Question 6

GFR

Answer 6

glomerular filtration rate. total filtrate/minute by both kindeys.

norm 125ml/min about 180L/day= 45 gals

Question 7

mechanisms that regulate rate of filtration

Answer 7

1. renal autoregulation: intrinsic vasoconstriction/dilation
2. angiotensin II: stimulates thirst center of hypothalamus. is a vasoconstrictor reduces vol of circulatory sys to keep blood pressure up. stimulates adrenal gland to make aldosterone to make kidneys retain Na and water
3. Renin: converts angiotensinogen into I made by justaglomerular apparatus. senses blood pressure to produce more renin. macula densa cells inhibit renin production somehow
4. ADH. mady by supraoptic nucleas of hypothalamus: water retention/maintain blood pressure. affects collecting ducts in kidney to reabsorb more water
5. neuro regulation: sympathetic extreem stress causes vasoconstriction of afferent to slow filtration. regular stress sympathetic causes vasoconstriction of both aff/efferent to maintain pressure and slow flow at the same time

Question 8

erythropoitin

Answer 8

made by kidney: regulates bloodcell production in bone marrow. RBC production when O2 delivery is lower

Question 9

calcitriol

Answer 9

final step in converting vitamin D to calcitriol occurs in kidneys. vital for absorption of Ca, Mg and hydrogen phosphate ions

Question 10

gradient that moves water in kidneys caused

Answer 10

1. 80% of ATP used by kidneys caused by active transport of Na out of filtrate
2. sodium reabsorbtion by osmosis 65% water and salt reabsorbed in proximal convoluted tubes.