Molecules that move down a concentration gradient and require transport proteins to cross a membrane
How does the sodium-potassium pump work to transport sodium and potassium against their concentration gradients?
ATP hydrolysis provides the energy to transport ions against their concentration gradient.
Which phospholipid membrane is least permeable to glycerol?
one with long and saturated fatty-acid tails
Involving planar bilayers, a solution of table salt (sodium and chloride ions in water) is added on the left side a membrane while pure water is added on the right side. After 30 minutes the right side tests negative for ions. This means?
Ions cannot cross planar bilayers.
What is the most likely mode of action of gramicidin? (Gramicidinis an antibiotic that increases the permeability of bacterial cell walls to inorganic ions)
It forms a channel in the membrane.
What do Sodium-potassium pumps do?
move two potassium ions and three sodium ions while consuming an ATP for each cycle