How many capillaries in glomerulus? What are they like? How much more permeable than typical capillaries?
50, fenestrated (pores) that make them 100-1000 times more permeable.
Have higher blood pressure bc afferent arteriole is larger than efferent. arteriole.
What's the glomerular capsule or Bowman's capsule? What's special about each layer?
A double-walled cuplike structure.
Inner layer - composed of podocytes. The fluid goes between the podocytes!
How much glomerular filtrate is produced a day? Why so much?
180 L or 45 gallons
High hydrostatic pressure of blood (45 mmHg - 60 mmHg instead of 10-30 like in other capillaries)
Also bc of number of pores.
The rate of glomerular filtration rate depends on?
The sizes of the arterioles going into glomerulus and out of it. Size is controlled by extrinsic (sympathetic nerves) and intrinsic (locally produced chemicals).
Acute renal failure?
Sudden loss of kidney function, usually associated w/ shock or intense renal vasoconstriction.
Inflammation of urinary bladder
Blood in urine
a method of clearing waste products from the blood in which blood passes by the semipermeable membrane of the artificial kidney and waste removed by diffusion
Night urination (during sleep)
The condition of having urinary volumes of less than 500 mL per day
retention of urinary constituents in the blood, owing to kidney disfunction
The proximal and distal convoluted tubules are made of what epithelium? Microvilli?
They have a single layer of cuboidal cells and prox. has microvilli to increase surface area, dist. has fewer microvilli.
What cell type is nephron loop composed of?
Flat squamous cells that lack microvilli
What's glomerular filtration rate per minute, hour, and day?
What does not pass through pores in glomerular capillaries?
Plasma proteins, RBC, WBC, and platelets bc they're too big to get through pores
How do you calculate GFR (glomerular filtration rate)?
urine formation rate (ml/min) x inulin conc. in urine (mg/ml)/
inulin conc. in plasma (mg/ml)
How much urine excreted per day? how much of filtrate reabsorbed?
Where does tubular reabsorption primarily occur?
In proximal convoluted tubule.
How much of glucose reabsorbed? Normal conc. of glucose in plasma?
100mg/100mL of plasma
What is transport maximum for glucose?
Tm is conc. of transported moleules needed to saturate the carriers and thus achieve max. transport rate. The Tm for glucose is 375 mg/minute filtered. Glucose above that will appear in urine (diabetes)
What percentage of reabsorption and where is under ADH control?
13% @ the distal conv. tubule and collecting duct
Common substances secreted by peritubular capillaries into the tubules are:
H+, K+, food additives, pesticides, and penicillin
What is net result of acidosis?
H+ ions excreted in urine, Na+ and HCO3- retained
What is net result of alkalosis?
H+ ions retained and bicarbonate excreted
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