Term | Definition |
cell | basic unit of structure and function |
unicellular | having only one cell |
multicellular | having many cells |
growth | becoming larger |
development | changing during an organism's lifetime, producing a more complex organism |
reproduce | produce offspring that are similar to the parents |
asexual reproduction | only one parent is involved; produce clones (identical to parents) |
sexual reproduction | reproduction involving two parents, combining genetic material to produce a new organism that differs from both parents |
spontaneous generation | the belief that life came from non-living things |
homeostasis | maintenance of stable internal conditions |
autotrophs | make their own food |
heterotrophs | cannot make their own food, so must consume food for energy |
microscope | instrument that makes small objects look larger |
cell theory | widely accepted explanation of the relationship between cells and living things |
organelles | tiny structures that carry out specific functions within a cell |
cell wall | rigid layer that supports the cell and acts like bones |
cell membrane | controls what enters and leaves the cell |
nucleus | control center of the cell |
chromatin | thin strands of material that fill the nucleus; DNA |
ribosomes | small grain-shaped organelles that make proteins |
eukaryotes | organisms with cells that contain a nucleus |
prokaryotes | organisms with cells, without a nucleus |
cytoplasm | thick, gel-like fluid that fills the cell; supports organelles |
mitochondria | powerhouse of the cell |
endoplasmic reticulum (ER) | tubules that help make proteins |
vacuole | stores water and other materials needed by the cell; or stores wastes |
chloroplasts | captures energy from sunlight and makes it into usable energy for the cell, via photosynthesis |