ions and water part 2

Question 1

what are the 6 roles of the kidney

Answer 1

ion balance
osmotic balance
blood pressure
pH balance
excretion of metabolic waste
hormone production

Question 2

what is the functional unit of the kidney

Answer 2

the nephron

Question 3

what is the nephron composed of

Answer 3

vasculature - glomerulus (capillary beds)

renal tubule - lined with transport epithelium

Question 4

what are the four renal processes

Answer 4

filtration
reabsorption - specific molecules in filtrate removed
secretion - specific molecules removed from blood and added to filtrate
excretion- urine excreted from the body

Question 5

what makes up the filtration structure of the glomerular capillaries

Answer 5

podocytes with foot processes

Question 6

what controls the blood pressure at the glomerulus

Answer 6

mesangial cells

Question 7

what is the renal threshold limited by

Answer 7

number of transporters

Question 8

what is primary urine

Answer 8

the initial filtrate in bowman capsule

isosmotic to blood

Question 9

function of proximal tubule

Answer 9

solute and water reabsorption

Question 10

loop of hence function

Answer 10

descending limb- water reabsorption

ascending limb- ion reabsorption

Question 11

distal tubule function

Answer 11

reabsorption completed for solutes and water

Question 12

collecting duct

Answer 12

regulation of final urine composition
drains multiple nephrons
carries urine to renal pelvis

Question 13

what is the difference in epithelium thickness along descending and ascending limbs

Answer 13

descending limb - very thin flat cells

ascending limb- very thick, microvilli, transporters

Question 14

where does most reabsorption of solutes and water take place

Answer 14

proximal tubule

also carries out secretion

Question 15

permeability of loop of henle

Answer 15

descending limb- permeable to water

ascending limb- impermeable to water

Question 16

transport in distal tubule

Answer 16

reabsorbs salts and water

secretes potassium

Question 17

function of parathormone on distal tubule

Answer 17

increases Ca reabsorption

Question 18

function of aldosterone on distal tubule

Answer 18

increases K secretion and Na reabsorption

Question 19

function of vasopressin on distal tubule

Answer 19

increases water reabsorption

Question 20

what are the three main forces that determine glomerular filtration rate

Answer 20

glomerular capillary hydrostatic pressure
bowman capsule hydrostatic pressure
oncotic pressure - osmotic pressure due to protein concentration in blood

Question 21

what are the three regulators of glomerular filtration rate

Answer 21

myogenic regulation
tubuloglomerular feedback
mesangial control

Question 22

what affect does myogenic regulation have on GFR

Answer 22

constriction/dilation of afferent arteriole

Question 23

what affect does tubuloglomerular feedback have on GFR

Answer 23

• juxtaglomerular apparatus
  macula dense cells in distal tubule control diameter of afferent arteriole
  juxtaglomerular cells in afferent arteriole

Question 24

what affect does mesangial control have on GFR

Answer 24

altered permeability of glomerulus