lecture 10 Flashcards
what is osmotic pressure
pressure that draws water by dissolved ions
what is high osmotic pressre
more water, less solute
what is low osmotic pressire
less water, more solute
does ion equilibrium happen in animals
no - energy input is needed to balance ions
what are the primary and secondary regulators of volume and ions
primary - gills
secondary - kidneys, do not deal with monovalent ions
what is osmolarity
the measure of osmotic concentration in mOsm
what is the osmolarity of FW
1-10 mOsm
what is the osmolarity of SW
1000 mOsm
describe the hag fish and how it regulates ion concentration
most primitive fish, do not have a jaw, raspar sucks on fluid (parasitic fish)
the only vertebrate that has the same osmolarity as SW
have slime glands
what are the holes on the side of lampreys for
to breathe (gill slits) while they are feeding with raspar
what is osmoconformity and what are its pros and cons
body fluid at different pressure than water
pro: cells surrounded by the same pressure
con: use ATP, gain and loss of ions
what is osmoregulation and what are its pros and cons
following pressure of water
pro: not expensive
con: cells exposed to different pressures
where would you normally see a change in pressure
brackish water
what is hypo and hyperosmoregulation
hyper = above pressure
hypo = below pressure
what is a good regulator
shrimp
what is a good conformer
mussel
what is a good semi-conformer
crab - regulates until 1100 mOsm, then conforms
where would you see osmolarity higher than SW
tidepools
describe FW teleost and their problems
hyperosmotic regulators
body = 290 mOsm, water at 10 mOsm
problems: gain of water by osmosis, loss of ions through diffusion
what is the water problem in FW teleosts and what are the solutions
gaining too much water through osmosis
kidneys produce high volume dilute urine
what is the ion problem in FW teleost fish and what are the solutions
ion loss in dilute water
gills have sodium-proton exchanger and chloride-bicarbonate exchanger
what are the functions of the gills
ion regulation, pH regulation, ventilation and gas exchange
describe the hydration of CO2
CO2 - carbonic acid - bicarbonate and proton
describe the SW teleost fish (what regulator is it) and its internal pressures
hyporegulator
body = 330 mOsm, SW = 1000 mOsm
what is the water problem for SW teleost fish
losing too much water through osmosis
solution: drink more water , produce little urine
what is the ion problem for SW teleost fish and what are the solutions
gain of ions through diffusion
two pavement cells around one chloride cell
Na-K-ATPase pump moves 3 Na out and 2 K in - Na-2K-Cl co transporter moves said number of ions into the CC, where Na goes back to ATPase pump - Cl leaves via Cl channel on apical membrane, goes to boundary layer - negative charge causes Na to leave . the cell through electrical gradient - all K leaves through K channels on basolateral membrane into ECF
what are the two types of ions in SW fish and where are they lost
divalent = feces or urine
monovalent = Na and Cl across gills
what are the two types of membranes in the SW ion mechanism
basolateral membrane and apical membrane
