click below
click below
Normal Size Small Size show me how
cells
VOCAB
| Term | Definition |
|---|---|
| Cell | the smallest structural and functional unit of an organism, typically microscopic and consisting of cytoplasm and a nucleus enclosed in a membrane. Microscopic organisms typically consist of a single cell, which is either eukaryotic or prokaryotic. |
| Cell theory | the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells. |
| Organelle(s) | Any of a number of organized or specialized structures within a living cell. |
| Organism | A living thing that has an organized structure, can react to stimuli, reproduce, grow, adapt, and maintain homeostasis. |
| Cytology | A branch of biology that studies the structure and function of plant and animal cells. |
| Nucleus | a membrane bound structure that contains the cell's hereditary information and controls the cell's growth and reproduction |
| Diffusion | the movement of a fluid from an area of higher concentration to an area of lower concentration |
| Osmosis | The tendency of a fluid, usually water, to pass through a semipermeable membrane into a solution where the solvent concentration is higher, thus equalizing the concentrations of materials on either side of the membrane |
| Active transport | the movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy. |
| Phagocytosis | the ingestion of bacteria or other material by phagocytes and amoeboid protozoans. |
| Pinocytosis | a mode of endocytosis in which small particles suspended in extracellular fluid are brought into the cell through an invagination of the cell membrane, resulting in a suspension of the particles within a small vesicle |
| Semi-permeable | (of a material or membrane) allowing certain substances to pass through it but not others, especially allowing the passage of a solvent but not of certain solutes. |
| Mitochondria | Cellular respiration |
| Ribosome(s) | proteins are made here |
| Cell wall | a rigid layer of polysaccharides lying outside the plasma membrane of the cells of plants, fungi, and bacteria. In the algae and higher plants it consists mainly of cellulose. |
| Viruses | a small infectious agent that replicates only inside the living cells of an organism. |
| Centriole(s) | a minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division. |
| Chloroplast(s) | (in green plant cells) a plastid that contains chlorophyll and in which photosynthesis takes place. |
| Phylum | a level of classification or taxonomic rank below kingdom and above class |
| Endoplasmic reticulum | a network of membranous tubules within the cytoplasm of a eukaryotic cell, continuous with the nuclear membrane. It usually has ribosomes attached and is involved in protein and lipid synthesis. |