Cellular Transport Lab Terms

Simple diffusion

movement of a substance directly across the phospholipid bilayer

what is the rate of transport proportional to?

membrane permeability, total surface area of the membrane, and the difference in concentration on either side of the membrane

at equilibrium a solutions entropy is __ and free energy is __

higher, lower

facilitated diffusion

movement of substances through the membrane that requires a transport protein

osmosis

movement of water across the membrane

active transport

any form of membrane transport that requires energy input in the form of ATP and a carrier protein

What movement is active transport in relation to the concentration gradient?

Against

specific forms of active transport

primary, secondary, endocytosis/exocytosis

osmolarity

describes the difference in solute concentration between 2 solutions

isosmotic

solutions have the same concentration, iso = same

hyperosmotic

solution A has a higher concentration than solution B, hyper = higher

hypoosmotic

Solution A has a lower concentration than solution B, hypo = less than

tonicity

the ability of an extracellular fluid to influence osmosis across the membrane and what happens to the cell when it is placed in a fluid where osmosis occurs

lysis (tonicity)

fills up with water, potentially burts

crenation

shrivel up in size, water leaves

Important things to consider when discussing tonicity…

tonicity refers to the solution that is influencing the cell size/shape and it only considers non-penetrating solutes

percent solution

mass/volume or volume/volume

molarity (M or mol/L)

unit of concentration, the number of moles of solute per liter of solution

moles of solute

mass of solute/molecular weight of solute