science Flashcards
cell
the smallest structural and functional unit of an organism
nucleaus
a dense organelle present in most eukaryotic cells
cytoplasm
the material or protoplasm within a living cell, excluding the nucleus.
cell membrain
the semipermeable membrane surrounding the cytoplasm of a cell.
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.
Mitochondria
an organelle found in large numbers in most cells, in which the biochemical processes of respiration and energy production occur. It has a double membrane, the inner layer being folded inward to form layers
cloraplast
a plastid that contains chlorophyll and in which photosynthesis
Golgi complex
is a cytoplasmic organelle.
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.
Ribosome
a minute particle consisting of RNA and associated proteins, found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.
Lysosome
an organelle in the cytoplasm of eukaryotic cells containing degradative enzymes enclosed in a membrane.
Vacuole
a space or vesicle within the cytoplasm of a cell, enclosed by a membrane and typically containing fluid.