Transport Specifics Flashcards
When does simple diffusion into the cell through the lipid bilayer occur?
when solute concentrations are greater on the inside of the cell than on the outside
What is facilitated diffusion through a specific transporter?
Passive diffusion with the use of a transporter protein that will only allow specific molecules/ions into the cell
What is facilitated diffusion through a nonspecific transporter?
passive diffusion with the use of a transported protein that will let any molecule/ion into the cell
What is osmosis?
the moevement of water into and out of the cell based on a concentration gradient
What are aquaporins used for?
they selectively conduct water into and out of the cell during osmosis while preventing other solutes or ions from entering or exiting the cell
What two ways can water move into and out of the cell during osmosis?
through the lipid bilayer and through an aquaporin
How is the osmotic relationship between cells and their environment determined?
by the relative concentrations of the solutions on either side
What does isotonic mean?
the water concentration is equal inside and outside of the cell
When a cell is isotonic with its environment, rates of diffusion are _________ in both directions
equal
what does hypotonic mean?
Higher solute concentration inside of the cell than outside
in a hypotonic scenario, net water diffusion is _______ the cell
into
WHat occurs during the diffusion of water into a hypotonic cell?
the protoplast swells, and pushes tightly against the wall, the wall prevents it from bursting
What does hypertonic mean?
solute concentrations are greater iutside of the cell than inside the cell
when a cell is hypertonic, net water diffusion is _____ the cell
out of
what is plasmolysis, when does it occur?
when water diffuses out of the cell and shrinks the protoplast away from the cell wall. This occurs when a cell is hypertonic with its environment.
