a single-celled organism that does not have a nucleus or membrane-bound organelles; includes bacteria


organism made up of cells that have a nucleus enclosed by a membrane; includes protists, animals, plants, and fungi


one of the small structures found in the cytoplasm of a cell and that perform a specific function


a membrane-bound organelle that contains the cell's DNA and controls its functions

plasma membrane

a phospholipid bilayer that covers a cell's surface and acts as a barrier


organelle that is the site of protein synthesis


the fluid between the cell membrane and the nucleus, and the organelles it holds


organelle is the site of cellular respiration which produces ATP


organelles found in plants and algae where photosynthesis occurs

selective permeability

property of a membrane that allows some materials to pass through while keeping others out


the movement of particles from regions of higher to lower concentrations


the diffusion of water across a selectively permeable membrane


solution where the concentration of dissolved materials inside and outside the cell is equal; causes no change in cell size


a solution where the concentration of dissolved material inside the cell is higher than outside, causing the cell to swell


a solution where the concentration of dissolved material outside the cell is higher than inside, causing the cell to shrink

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