| Term | Definition |
| lipid bilayer | structure of membrane, two sheets of lipid molcules with tails pointed inward, proteins embedded in bilayer (serve as channels) along with carbohydrate molecules (id markers - recognition) |
| hypertonic | having a higher concentration of solute than another solution |
| hypotonic | when comparing two solutions, the solution with the lesser concentration of solutes |
| isotonic | used of solutions) having the same or equal osmotic pressure |
| passive transport | The movement of materials through a cell membrane without using energy |
| diffusion | process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated |
| osmosis | diffusion of water through a selectively permeable membrane |
| selectively permeable | a property of cell membranes that allows some substances to pass through, while others cannot |
| faciliated diffusion | The passive transport of ions or molecules by a specific carrier protein in a membrane |
| concentration gradient | a difference in the concentration of a substance across a space |
| active transport | energy-requiring process that moves material across a cell membrane against a concentration difference;the movement of materials through a cell membrane using energy |
| endocytosis | process by which a cell takes material into the cell by infolding of the cell membrane; is an |
| exocytosis | process by which a cell releases large amounts of material |
| Mitosis | cell division in which the nucleus divides into nuclei containing the same number of chromosomes |
| meiosis | (genetics) cell division that produces reproductive cells in sexually reproducing organisms |
| haploid | term used to refer to a cell that contains only a single set of chromosomes and therefore only a single set of genes |
| diploid | cells having two sets of chromosomes |