Excretion Flashcards
excretion purpose
how animals get rid of the nitrogen containing waste products of metabolism
isoosmotic
two solutions are separated by a selectively permeable membrane have the same osmolarity and no net movement
hyperosmotic
with two solutions, the one with the greater concentration of solutes
hypoosmotic
with two solutions, the one that is more dilute or has a lower concentration of solutes
stenohaline
most animals cannot tolerate substantial changes in external osolarity
euryhaline
animals that can survive large fluctuations in external osmolarity such as salmon and tilapia
marine fish osmolarity
marine fishes constantly lose water by osmosis and gain salt by diffusion
marine fish h20 balance
after drinking seawater chloride ions are actively transported out through the gills and kidneys do the rest
anhydrobiosis
invertebrate animals such as tardigrades survive for up to 10 years in dehydrated state
transport epithelia
layer or layers of specialized epithelial cells that regulate solute movements
albatross transport epithelia
nasal salt glands that drip salt solution saltier than seawater
freshwater fish transport epithelia
gills of freshwater fish use active transport to move salts from dilute surrounding water into blood
nitrogenous waste
breakdown of macromolecules produces ammonia, which is a very toxic molecule
ammonia waste
mostly freshwater aquatic animals because ammonia can be tolerated at very dilute levels
urea
in liver combines ammonia with carbon dioxide and is used by mamals, most amphibians, sharks, some marine fishes
uric acid
insoluble in water and costs lots of ATP; insects, land snails, reptiles, birds
egg waste
uric acid can since insoluble in water can be secreted in eggs and not harm animal
excretory filtration
tubule collects filtrate from blood including water and solutes pushed by blood pressure
excretory reabsorption
transport epithelium reclaims essential substances and returns to capillary
excretory secretion
toxins and excess ions are pumped from blood by active transport into filtrate tubule
excretory excretion
filtrate leaves the body as waste
protonephridia
excretory system of flatworms with network of dead end tubules lacking internal openings
flame bulb
interstitial fluid filters through cap cell membrane and beating cilia pushes waste towards body wall
nephridiopore
waste empties out of protonephridia through this opening in flatworm
metanephridia
earthworms have these tubules that are the waste filtering system
nephrostome
fluid enters the metanephridia through this from coelemic fluid
nephridiopore
the bladder and earthworm excretion system exits here
malphigian tubes
insects and terrestrial arthropods have waste removal with tubes open in waste and closed ends in hemolymph collecting salt, water, nitrogenous waste with reabsorption at rectum
nephron
a single long tubule with a ball of capillaries called the glomerulus
bowmans capsule
beginning of the tubule in the nephron which surrounds the glomerulus
juxtamedullary nephrons
well developed loops of henle found in 20% of human nephrons and only in mammals and birds
loop of henle
hairpin turn that extends deeply into the renal medulla with a descending and ascending limb
renal cortex
outside of the nephron where a proximal and distal tubule are located
renal medulla
inside of nephron where the loop of henle and collecting duct are located
afferent arteriole
branch of the renal artery that enters the glomerulus
efferent arteriole
arterioles that leave the glomerulus
peritubular capillaries
capillaries that surround the proximal and distal tubules
vasa recta
capillaries that surround the loop of henle
proximal tubule filtrate
transport epithelium allow the transfer of Na-Cl with water; transport of toxins and NH3 into the tubule
descending loop of henle
transport epithelium is permeable to water but not to salt, which concentrates the filtrate
ascending loop of henle
transport epithelium is permeable to salt but not water and upper portion actively transport salt, which concentrates interstitial fluid and lowers osmolarity of renal medulla
collecting duct
water is lost to the hyperosmotic interstitial fluid as transport epithelium is not permeable to salt
