movement of materials without the use of the cell's energy
the movement of ions or molecules across a cellular membrane from a lower concentration to a higher concentration, requiring energy
The movement of molecules or ions from a region of higher concentration to a region of lower concentration
Separates cell from its environment. Controls movement of substances into / out of the cell
The diffusion of water across a selectively permeable membrane.
Water concentration inside the cell is equal to the water concentration outside the cell
Involves the intake of a small droplet of extracellular fluid
Involves the intake of a large droplet of extracellular fluid which has large particles in it (i.e. bits of organic matter or bacteria)
Receptor assisted endocytosis
Involves the intake of specific molecules(ex. Cholesterol) through the aid of special membrane proteins
The reverse of endocytosis. Involves the movement of a vesicle from inside the cell to the cell surface in which its contents are excreted into the surrounding environment (ex. Insulin secreted by pancreatic cells)
contain a high concentration of solute relative to another solution (e.g. the cell's cytoplasm). When a cell is placed in this solution, the water diffuses out of the cell, causing the cell to shrivel.
contain a low concentration of solute relative to another solution (e.g. the cell's cytoplasm). When a cell is placed in this solution, the water diffuses into the cell, causing the cell to swell and possibly explode.