Human Phyys Final Exam glomerular filtration and tubular transport

3 processes of urine formation

filtration

reabsoption

secretion

filtration

bulk movement of plasma into bowman’s space

none selective by size

reabsorption

movement of substances from tubule to blood

secretion

movement of substances from blood to tubule

tubular transport

provide seelctivity

structure of glomerular filtration barrier

fenestrated glomerular capillary endothelium

neg charge basement mem

prodocyte slit diaphragms

size and charge

determine filtration

glomerular filtration barrier

prevents filtration of proteins and cells

starling forces

PGC

PBS

piGC

glomerular hydrostatic pressure PGC

promotes filtration

bowman’s psace preassure PBS

opposes filtration

plasma oncotic pressure piGC

opposes filtration

net filtration pressure

drives fluid movmeent

starling forces

determines GFR

GFR

volume of plasma filtered per min

depends on filtation pressure and surface area

indicator of kidney func

est using creatine clearance

tubular reabosrption

majority= filtrate

through tranport proteins

driven by electrochem gradients

water

follows osmotic gradients

peritubular capillaries

receive reabsorbed substances

proximal tubule reabsorption

filtered Na and h20, glucose and aa

driven by na’k atpase gradient

includes secondary active transporters

site of bulk recovery

tranporters

finite capacity

when saturated

solute remains in filtrate

tubular secretion

movment of blood to tubular fluid

removes drugs, toxins, ions

mainily in proximal tubule

use active tranport mech

enhance elimination of substances

peritbular capillaries

surround renal tubules

low hydrostatic pressure

high oncotic pressure

strongly favors reabosrption

return solutes to circultation

filtration

determines intial filtrate comp

reasbroption

recovers valuable mol

secretion

removes additional waste

urine

reflects combined process

changes in filtration, reabosrption, secretion

aler urine comp