week 9 Flashcards
(20 cards)
name the 3 layers of the kidney
renal cortex- outer
renal medulla- inner (renal pyramids/renal columns)
renal pelvis- deepest part (drains urine into bladder)
how does the kidney receive blood?
renal artery/vein supplies blood, connects with ureter at renal hilum
what are the 2 main parts of a nephron?
renal corpuscle, renal tubule
describe the renal corpuscle
- glomerulus, glomerular capsule (space with podocytes and filtration slits)
- blood enter afferent arteriole, exit efferent arteriole
describe the renal tubule
- proximal convoluted tubule, nephron loop, distal convoluted tubule
- (to collecting duct, renal pelvis)
what layer of the kidneys are the renal corpuscle, proximal/distal tubules, and nephron loops in?
renal corpuscle, proximal/distal tubule in the renal cortex
nephron loops in renal medulla
what are the 2 types of nephrons and describe them?
cortical
- short nephron loops, minimal in medulla
juxtamedullary
- long loops, deep
- can produce highly concentrated urine
describe blood flow through the kidney
renal artery, afferent arteriole (glomerulus), lots of plasma enters glomerular capsule, efferent arteriole, peritubular capillaries/vasa recta
second set of capillaries reabsorbs fluid, blood (waste-free) flows to venules/veins, renal vein
what are the 3 processes of urine formation?
filtration, reabsorption, secretion
explain the process of filtration
- at renal corpuscle
- water and solutes filtered from blood into glomerular capsule
- glomerular filtration rate to regulate blood volume/urine output
explain the process of reabsorption
- from renal tubule (branching off glomerular capsule) to capillaries
- most in proximal convoluted tubule
- active transport: sodium, glucose
- passive transport (osmosis): water
- aquaporins (channel proteins) aids
explain the process of secretion
- from capillaries to collecting duct
- reverse reabsorption
- most in proximal convoluted tubule
- waste pumped from capillaries to renal tubule
why is there a small movement of water out of blood into glomerular capsule in filtration?
hydrostatic pressure pushes water out, osmotic pressure pulls water in but hydrostatic is stronger
describe reabsorption and secretion in the renal medulla
passive processes in thin limbs of nephron loop
active sodium reabsorption in thick ascending limb parts
this causes salty interstitial fluid
what are the hormones that regulate kidney function?
aldosterone, atrial natriuretic peptide, antidiuretic hormone
what does aldosterone do and what is the role of renin?
sodium reabsorption, potassium secretion (sodium up, potassium down, volume up in blood)
renin produced due to low blood pressure by kidney-converts angiotensinogen to angiotensin, raise blood pressure, stimulate aldosterone secretion
what does atrial natriuretic peptide do?
decrease blood pressure (low sodium/water reabsorption)
increase urine vol
what does antidiuretic hormone do?
lower osmolality (concentration) of blood
increase water reabsorption, produce concentrated urine
how is pH controlled in the blood?
bicarbonate ions fix acidic
hydrogen ions fix alkaline
excretion/reabsorption in proximal convoluted tubule
how is urine stored and released?
store in bladder
ureters connect kidney to bladder (peristalsis to move urine)
urethra connects bladder to outside
