Cell Transport Flashcards
page 50-51
What is diffusion, and how does it occur?
The movement of molecules from high to low concentration.
Define osmosis and provide an example.
The movement of water molecules from low to high solute concentration. Example: water entering a plant cell.
How does facilitated diffusion differ from simple diffusion?
It involves membrane proteins to transport large or charged molecules.
What is active transport, and why does it require ATP?
It moves substances against a concentration gradient, using energy from ATP.
Describe the process of endocytosis.
The plasma membrane engulfs material to form a vesicle for internal transport.
How does the sodium-potassium pump work?
It moves sodium out of the cell and potassium into the cell using ATP.
Compare pinocytosis and phagocytosis.
Pinocytosis engulfs fluids; phagocytosis engulfs larger particles or cells.
What is exocytosis, and why is it important?
The release of substances from a cell via vesicles; it removes waste or secretes molecules like hormones.
What role do channel proteins play in facilitated diffusion?
They allow specific molecules to pass through the membrane.
