anatomy Flashcards
nephron: recall the constituent parts of a nephron and which compounds are absorbed in each area, explain the microscopic anatomy of the Bowman's capsule and list the regional features of tubular cells aiding urinary concentration, identify different sections and cell types of the nephron in light and electron microscopic images
what are 3 components of renal corpuscle
Bowman’s capsule, glomerulus consisting of capillaries, podocytes associated with glomerulus
where is the blood supply to in the renal corpuscle
vascular pole of corpuscle
where does blood enter in and exit from
afferent, then efferent, arterioles
how is blood filtered, including features which assist filtration
passes through glomerulus at high pressure from renal artery; high surface area, fenestrated capillaries, modified basement membrane, podocytes with feet which interdigitate
effect of hypertension on blood filtering in glomerulus
protein in urine
how is a pressure gradient created in glomerulus
afferent arteriole big, efferent arteriole small
what does the filtrate consist of
all components below 50000 RMM, keeping cells in bloodstream, so is isotonic
where is filtrate drained into proximal convoluted tubule
urinary pole of corpuscle
what % of glomerular filtrate are reabsorbed in proximal convoluted tubule
70%
5 materials reabsorbed by proximal convoluted tubule and brief method
Na+ uptake by basolateral Na+ pump, water and anions follow Na+, glucose uptake by Na+/glucose co-transporter, amino acid uptake by Na+/amino acid co-transporter, protein uptake by endocytosis (many vesicles)
type of proximal convoluted tubule epithelium
cuboidal
what is proximal convoluted tubule epithelium sealed with
fairly water-permeable tight junctions
why is there also not a huge influx/efflux of water at the proximal convoluted tubules
iso-molar filtrate
how is membrane area of proximal convoluted tubule increased to maximise rate of resorption
brush border at apical surface, interdigitations of lateral membrane
what does proximal convoluted tubule contain to allow some water diffusion
aquaporins
why do proximal convoluted tubule have prominent mitochondria
high energy requirement
what is the main function of loop of Henle and vasa recta blood vessels
creation of hyper-osmotic extracellular fluid
what is descending thin limb of loop of Henle made from
simple squamous epithelium
what do aquaporins in descending thin limb of loop of Henle allow
passive osmotic equilibrium
what are actively pumped out of tubular fluid in ascending thick limb of loop of Henle
Na+. Cl-
what is ascending thick limb of loop of Henle made from, and what does it have few of
cuboidal epithelium with few microvilli
how does ascending thick limb of loop of Henle have a very low water permeability
very water-impermeable tight junctions, membranes also lack aquaporins
what does a very low water permeability in ascending thick limb of loop of Henle result in
hypo-osmotic tubular fluid, hyper-osmotic ECF to allow movement of ions passively out of descending thin limb of loop of Henle
why are there prominent mitochondria in ascending thick limb of loop of Henle
high energy requirement
