Excretory System Flashcards
(55 cards)
role of liver, what it deals with, what it makes
deals with hydrophobic large products kidney cant filter and makes bile. also makes urea with excess nitrogen
3 main roles of kidney
excretion of hydrophilic waste, maintain solute concentration and pH, maintain fluid volume
vaopressin, where released from, what it is, what it does
peptide hormone, released from posterior pituitary, makes collecting ducts permeable to water via aquaporins
renal vein, renal artery, ureter
renal vein has purified blood from kidney, renal artery is how blood enters kidney, ureter is urine’s path to bladder
internal and external sphincter
internal is involuntary smooth muscle, external is voluntary skeletal muscle
filtration, where it occurs
cells and protein remain in blood, water and small molecules move to renal tubule
occurs via golumerulus capillaries and bowman’s capsule
secretion and absorption, where occurs, what we take back and excrete
takes back useful things via active transport from peritubular capillaries (which drain into renal vein, vena cava)
secretes drugs if in urine
urine concentration, where it happens
happens at DCT distal convoluted tubule(regulated by hormones) and collecting duct
how ADH and aldosterone work, which is inhibited by alcohol
when dehydrated, ADH from posterior pituitary prevents diuresis, increases water reabsorption by making distal nephron permeable to water
ADH inhibited by alcohol
when blood pressure is low, aldosterone released from adrenal cortex to increase absorption of Na+ by distal nephron leading to thirst
pathway of blood into kidney before loop of henle, what happens when efferent arteriole constricts
renal artery - afferent arteriole - glomerulus cappilaries - efferent arteriole
when constricts fluid, leaks past glomerular basement membrane into Bowman’s Capsule
after glomerulus? goes to
proximal convoluted tubule: reabsorbs water, ions, glucose and amino acids by secondary transport
loop of henle: dips into medulla from cortex
descending loop water exits filtrate
ascending loop active transport of Na+, K+, Cl- out of tiltrate
(vasa recta reclaims all these substances)
distal convoluted tubule: reabsorbs water and urea in response to ADH, reabsorbs Na+ in response to aldosterone
glomerular filtration rate depends on
pressure at JG cells (baroreceptors) at juxtoglomerular apparatus (structure formed by distal convoluted tubes and afferent arteriole
macula densa is, how it controls filtrate osmolarity
at junction of ascending loop and distal tubules that has chemoreceptors that monitor filtrate osmolarity, when low, stimulate JG cells
dilate afferent arteriole increases flow through glomerulus and increases glomerular filtration rate
what low bp stimulates - renin pathway
release renin enzyme used on angiotensinogen to make angiotensin I converted to angiotensin II with ACE leads to vasoconstriction and stimulates aldosterone
how kidney radiates pH
low pH, release HCO3-
role of calcitonin, where it releases from, its opposite hormone
released from C cells in thyroid gland
when Ca2+ too high, removes from blood by deposition in bone, reduces absorption in gut, excrete in urine
parathyroid hormone does the opposite
lumen of intestine layers from inside to outside
basolateral surface, tight junctions (separate body fluids from cellular environment), microvilli at apical surface
2 major nerve supplies of gut
myenteric plexus: control gut motility
submucosal plexus: regulate enzyme secretion, gut blood flow, ion/water balance
4 components of autonomic GI motility
automacity, functional synctium (like heart), has own enteric nervous system (branch of autonomic nervous system to help blood flow, gut movements, fluid exchange), controlled by hormones
endocrine vs exocrine hormones that are released to gut, where released from
endocrine, empty into nearby capillaries, released from islets of langerhans
exocrine, release into gut lumen and made by pancreatic acinar cells
pathway of food from mouth
mouth, pharynx, stomach, small intestine
digestion that happens at mouth level
fragmentation, lubrication, enzymatic digestion
saliva has salivary enzymes like amylase that breaks down starch, lingual lipase for fat, lysozyme for bacterial walls
components of pharynx
trachea and esophagus, with epiglottis in between so you don’t inhale food
digestion at stomach level
- gastric pH of 2
- pepsinogen secreted by chief cells in stomach wall go through acidic proteolysis and become pepsin, which breaks down protein
