| A | B |
|---|
| Cell theory states all living things are made | of one or more cells |
| Cell theory states cells are basic units of | structure and function in organisms |
| cell theory states all cells arise from | existing cells |
| homeostasis | maintenance of stable internal conditions |
| cell membrane | thin, flexible layer that surrounds the cell |
| function of cell membrane | where everything cell needs enters, wastes leaves |
| phospholipids | make cell membrane selectively pereamble |
| lipid bilayer | two layers of phospholipids in cell membrane |
| diffusion | particles spread from an area of greater concentration to area of lesser concentration |
| osmosis | the diffusion of water |
| passive transport | movement of substances in a cell that do not require energy, such as osmosis |
| facilitated diffusion | transport proteins and carrier proteins carry substances across cell membrane |
| active transport | cell must use energy to move materials across cell membrane |
| sodium-potassium pump | transports sodium ions out of cell and potassium ions into cell |
| endocytosis | cell membrane surrounds particle and fuses it into cell |
| exocytosis | a vesicle forms and opens to move large particles out of cell |
