Cell Transports Flashcards
Diffusion
movement of molecules from regions of high concentration to low concentration
Require energy? (diffusion)
It doesn’t require energy
Equilibrium
when the net concentration of molecules on each side of the membrane is equal
Osmosis
the movement of water molecules from a region of low solute concentration to a region of high solute concentration
Facilitated diffusion
Occurs when a substance is aided across a membrane by a protein channel
Require energy? (facilitated diffusion)
it doesn’t require energy as the molecules aren’t moving against their concentration gradient
Active transport
the movement of substances from a region of lower concentration to a region of higher concentration
Require energy? (active transport)
energy is required as movement is against a concentration gradient
Endocytosis
incorporation of substances from outside the cell into the cell as membrane-bound vesicles
3 forms of endocytosis
phagocytosis, pinocytosis, recpetor mediated
Phagocytosis
engulfment of solid molecules
Pinocytosis
engulfment of liquid particles
Receptor mediated
engulfment of specific particles according to membrane receptors
Exocytosis
releases substances from the inside of the cell to the outside of the cell.
How does exocytosis occur?
by fusion of a vesicle membrane with the plasma membrane. The vesicle contents are then released to outside the cell.
