biology practice test

what is the cell membrane

a selectively permeable barrier made of a phospholipid bilayer that surrounds the cell and regulates the movement of substances in and out.

what is the cell membrane structure

consists of a phospholipid bilayer with embedded proteins that help control what enters and leaves the cell.

passive transport

what is diffusion

the movement of particles from an area of high concentration to an area of low concentration.

what is osmosis

the movement of water across a partially permeable membrane from an area of low solute concentration to high solute concentration.

what is facilitated diffusion

the movement of substances across a cell membrane through transport proteins, from high to low concentration.

what is active transport

the movement of substances across a membrane from low to high concentration using energy.

what is endocytosis

the process of taking substances into the cell by forming vesicles from the cell membrane.

what is phagocytosis

a type of endocytosis where large particles are engulfed by the cell.

what is pinocytosis

a type of endocytosis where liquids are taken into the cell in small vesicles.

what is exocytosis

the process where materials are transported out of a cell in vesicles that fuse with the cell membrane and release their contents.

what are the effects of movement throughout the cell

to distribute nutrients, remove wastes, and maintain balance (homeostasis), allowing the cell to function properly.