Urinary system Flashcards
function urinary system
excretory system, maintain homeostasis
positive feedback
intensifies change ie oxytocin contraction
osmoregulation
regulates solute concentration and balances gain/loss water ie desert/marine animals face environment that can deplete body water
osmolarity
solute concentration determines mvt of water across selectivity permeable membrane
osmosis
diffusion of water accross semipermeable membrane from more dilute to less dilute
tonicity
ability solution change volume by osmosis
what happens to cell in hypotonic
cell expands: lysed
what are osmoconfromers and examples
osmolarity body fluids=sea: isotonic ie shark and marine invertebrates
osmoregulators
constant blood osmolarity
what does osmoregulators have oftened developped
mechanisms to cope with water balance
what do osmoregulators-freshwatre vertebrates do in hypertonic solution
adapted to rpevent water form enetring and transport ions back into their bodies
what do osmoregulators-marine vertebrates do in hypotonic solution
retain wtare by drinking seawater and eliminating excess ions through kidneys and gills
Osmoregulatory organs
- protonephridia: tubules in flatworm that extends in flame cells where cilia draws fluid
- Nephridia: tubules open inside outside
- Malpighian tubules: extension digestive tract in insects where tubules collect water and waste from circulatory system
- vertebrate kidneys: glomerulus filters blood, filtrate, waste products
kidneys made of waht and how many
nephrons, 1 million in 1 human kidney
Are marine vertebrates fluids hypo or hyper tonic
hypo so drink watre and ions transport by kidneys
are freshwater vertebrates and amphibians fluids hyper or hypo tonic
hypertonic so prevent watre enter by avoid drinking water and reabsorb ions across kidney tubules
marine vs terrestrial reptile kidney
marine reptile: excrete isotonic urine and salt (by salt glands)
terrestrial reptile: reabsorb salt and water in kidneys
meaning longer loop of henle
more water reabsorbtion
mammals and birds excrete and retain what
excrete concentrated urine and retain water
from where does kidney receive blood
renal artery
how does kidney maintian homeostasis (electrolyte and acid/base balance)
filtering blood, excreting urine
kidney regulates what hormones
ADH and aldopsterone
kidney syntehsizes which vitamin
D
3 (4)functions kidney
filtration: blood filtered out of glomerulus in tubule system
reabsorbtion: mvt solutes in blood
secretion: mvt substances
Excretion: nitrogenous wastes, excess K+,H
+ see paper
organs urinary system
ureters, urinary bladder, urethra
internal structure of kidney
renal cortex and renal medulla (medullary pyramids and renal columns)
Renin-angiotensin-aldosterone feedback mechanism 4 steps
1-drop blood pressure near glomerulus cause release enzyme renin
2-renin triggers formation peptide angiotensin II
3-Angiotensin II raises blood pressure and decrease blood flow to kidneys
4-release aldosterone increasing blood volume/pressure
countercurrent (positive feedback)
?
what makes conducting duct more permeable to water
ADH
dehydration triggers what
release of ADH which helps conserve water