Physiology

Question 1

what makes up a nephron

Answer 1

renal corpuscle + renal tubules

Question 2

what makes up the renal corpsucle

Answer 2

afferent arteriole –> bowen’s capsule (squamous cells) –> efferent arteriole

Question 3

components of the renal tubule

Answer 3

proximal convoluted –> loop Henle –> distal convoluted –> collecting duct

Question 4

function of proximal convoluted tubule

Answer 4

70% sodium + water // almost all glucose and amino acids

Question 5

structure + function loop of Henle

Answer 5

thick –> thin limb descending (water permeable) –> thin –> thick limb ascending (NaCl permeable)

Question 6

what is the vasa recta

Answer 6

loops of blood vessels that follow loops of Henle to reabsorb to blood stream

Question 7

function distal tubule

Answer 7

collects rest of Na via aldosterone

Question 8

function collecting duct

Answer 8

water reabsorption secondary to ADH action

Question 9

what marker is most accurate for eGFR

Answer 9

inulin

Question 10

what marker is commonly used to determine eGFR

Answer 10

creatine (rise = creatine shows poor GFR)

Question 11

what is clearance

Answer 11

rate at which plasma is cleared from a toxin - measure by creatine

Question 12

what measures renal plasma flow

Answer 12

PAH

Question 13

what measures renal plasma flow

Answer 13

PAH

Question 14

what triggers release of ADH

Answer 14

low BP –> decreased atrial stretch

Question 15

function ADH

Answer 15

increases permability to water in collecting duct –> reabsorbed

Question 16

when is ANP released and what is the function

Answer 16

released from atrium when increased stretch –> excrete Na (+water) –> decreased volume

Question 17

what controls rate of flow into nephrons

Answer 17

macula densa in distal tubule

Question 18

what cells secrete renin

Answer 18

granular cells in JXA

Question 19

what stimulates renin release

Answer 19

decreased pressure in afferent arteriole (reduced NaCl, reduced volume) // increased sympathetic activity (in response to low BP)

Question 20

RAAS system overview

Answer 20

renin converts angiotensinogen –> angiotensin I // ACE converts angiotensin I –> II // angiotensin II causes adrenal cortex to release aldosterone

Question 21

function aldosterone

Answer 21

increased reabsorption of Na + increased secretion of K

Question 22

what stimulates release of erythropoeitn

Answer 22

cellular hypoxia (lack of 02 in blood)

Question 23

what is osmolarity

Answer 23

concentration of osmotic particles in a solution

Question 24

what % of body water is ICF vs ECF

Answer 24

ICF = 66% // ECF = 33%

Question 25

components ECF

Answer 25

plasma, interstitial, transcellular

Question 26

maintenance fluid requirements (water, electroclytes, glucose)

Answer 26

water 25-30 ml/kg/day // na,K,cl = 1 mmol/kg/ day // glucose = 50-100g/day

Question 27

what does NICE recommend prescribing for routine maintenance only fluid in the first 24 hours

Answer 27

NaCl 0.18 in 4% water + 27 mmol/l K

Question 28

risks of too much 0.9% saline

Answer 28

risk of hyperchlorine met acidosis