Ch 22-23 Flashcards
describe how mitochondria are oxygen sinks
- mitochondria consume energy (less oxygen inside mitochondria)
- oxygen flows from high to low conc & so flows back into the mitochondria
(keep using oxygen so more keeps flowing in)
larger animals rely on ____ & ____ to drive gas exchange
bulk flow & diffusion to drive gas exchange
partial pressure _____ as you get deeper into the body & give example of pathway
partial pressure decreases
(being used at each step so decreases conc)
air - lungs - blood - mitochondria
dalton’s law of partial pressure
- pressure a specific gas exerts = partial pressure
- directly proportional to its % in a mixture
describe what happens to partial pressure at high altitudes vs underwater
high altitudes
= pressure drops, so partial pressure does as well (less oxygen is available to breathe in)
ex. still 21% of air but not enough for gas exchange now
underwater
= pressure increases, partial pressure increases
- weight of water plus air
- more gases dissolve in body now (N) and if come out of water too quick can form bubbles in blood as they’re leaving too fast
henry’s law
the amount of gas dissolved in a liquid is proportional to:
- partial pressure & solubility
as temperature of a liquid rises the solubility of gases _____
gases decreases
(ex. when boiling gases form bubbles to leave solution)
solubility of gases in liquid decreases with ______ salinity
increasing salinity
more salt = less gas dissolves
gases diffuse from areas of ___ partial pressure to areas of ___ partial pressure
high to low partial pressure
is the partial pressure the same for the gases in a liquid and in the air above the liquid ?
YES
(touching pp’s of gases are the same)
gas diffusion occurs more readily through ____ rather than ____
air rather than water
describe example of turtle next being flooded with water
water replaces spaces that were filled with air
- less oxygen available
- even though it can dissolve in water it does so MUCH LESS efficiently than in air, so partial pressure drops
gas molecules must be in ____ ____ form to contribute to partial pressure
free gas (unchanged) form
2 types of bulk flow & describe
- unidirectional
= one direction only, no reversal
ex. blood flow in vessels - tidal flow
= moves in and out
ex. lungs of mammals
what is bulk flow
movement of a large volume of fluid (air or water) from one place to another
describe the Prairie dog example
ambient winds help move oxygen and CO2 through their burrows
- this airflow reduces the effort required by animals to get O2 and CO2 making breathing easier in enclosed spaces
- pressure increases at point where air is entering, decreases pressure in burrow when it blows out
what should be used to short vs long has transports
short - diffusion
long - convection (bulk flow)
O2 is transported __ the gas exchange membrane ____ environmental medium ? what about CO2
TO the gas exchange membrane FROM enviro medium
*diffusion
CO2 = from, to enviro medium
*diffusion could also active transport
ideal diffusion has a ___ surface area and a ___ membrane
large SA and a thin membrane
CO2 can diffuse out into the enviro medium via diffusion but in some cases ……
it can be transported actively via bicarbonate anions
3 types of breathing structures
- lungs
- external gills (axolotl)
- internal gills (fish)
*come out from body but have a superficial body cavity
in mammals skin has ____ to gases ? what about frogs
mammals = low permeability to gases
frogs = has permeability to gases / uses skin and lungs to exchange O2 and CO2
