forces across membranes 3 Flashcards
osmosis
the net movement of water from an area of high conc to an area of low conc. via aquaporins.
what is osmosis determined by?
water has no barrier.
some solutes are selectively permeable across the membranes.
so water will move across barriers in order to ensure that the concentration of solute and water is the same on both sides of the particle. this implies that the compartment is expandable as the volume of water will change
osmotic pressure
the pressure required to prevent water movement
how is a mole measured. units
6.02x 10^23 molecules
concentration- how is it measured
moles/litre
why is concentration misleading in terms of osmosis?
one mole can dissociate into multiple particles.
define osmolarity and tonicity
osmolarity; the number of particles in a solution. measured in osmoles or milliosmoles/litre
tonicity: the number of non-penetrating particles in a solution. more important as it determine cell volume.
what is the osmolarity of plasma?
285 mosmol/litre
iso
hypo
hyper
iso= SAME
hypo= FEWER
hyper=MORE