KIDNEYS Flashcards
what is the function of the kidneys
to excrete waste (urea)
to regulate blood water potential
how does blood enter the kidneys
through the renal artery
where does ultafiltration tank place
the glomerulus and bowmans capsule
which arteriole takes blood into the glomerulus
afferent arteriole
which arteriole takes filtered blood away the glomerulus
efferent arteriole
how do you generate high pressure in the glomerulus causing ultrafiltration
The afferent arteriole (opening) is wider than the efferent arteriole (closing) therefore blood is at high pressure in glomerulus
what is passed onto bowmans capsule in ultrafiltration
liquid and small molecules into bowmans capsule
what are the 3 layers the liquid and small molecules have to pass through to get from the capillary to the bowmans capsule
the capillary wall
the basement membrane
epithelium of bowmans capsule
what is the glomerular filtrate and what does it consist of
the large molecules that can to fit through the membrane into the bowmans capsule and therefore stay in the blood
eg proteins and blood cells
what happens next to glomerular filtrate from stage 1
it passes along the nephron to the PCT (proximal convoluted tubule), loop of Henle and DCT (distal convoluted tubule) where selective reabsorption happens
what does the PCT wall have on it
microvilli
providing a large SA for the reabsorption of useful materials from the glomerular filtrate into the blood
What is reabsorbed along the PCT and how
glucose is selectively reabsorbed
by active transport and facilitated diffusion
what is urine made up of
water urea dissolved salts hormones excess vitamins
where is water reabsorbed
PCT
Loop of henle
DCT
Collecting duct
state 2 ways water is lost
urea
sweat