Lecture 23 Flashcards
Urine flows
Urine flows –> kidney –> down its ureter –> bladder –> the outside via the urethra
Urinary system =
kidneys, ureters, urinary bladder, and urethra
Filter:
the blood and return most of water and solutes to the bloodstream
Overview of Kidney Functions:
- Regulation of blood ionic composition, blood pH, osmolarity, and glucose, blood volume, blood pressure
- Release of erythropoietin and calcitriol
- Excretion of wastes & foreign substances
Regulation of blood ionic composition:
Na+, K+, Ca+2, Cl- and phosphate ions
Regulation of blood volume:
conserving or eliminating water
Regulation of blood pressure
- secreting the enzyme renin
- adjusting renal resistance
Drainage system fills
renal sinus cavity
Drainage system minor and major calyces…
empty into the renal pelvis which empties into the ureter
Blood & Nerve Supply of Kidney: Abundantly supplied with
- blood vessels
- receive 25% of resting cardiac output via renal arteries
Functions of different capillary beds:
- glomerular capillaries
- peritubular capillaries
- vasa recta
glomerular capillaries:
- where filtration of blood occurs
- vasoconstriction & vasodilation of afferent & efferent arterioles produce large changes in renal filtration
peritubular capillaries:
carry away reabsorbed substances from filtrate
vasa recta:
supplies nutrients to medulla without disrupting its osmolarity form
Blood & Nerve Supply of Kidney: regulate blood flow & renal resistance by altering arterioles
Sympathetic vasomotor nerves