Ch. 4 Vocab Cells Flashcards
A protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists; protects the cell and helps maintain its shape.
Cell Wall
The theory that all living things are composed of cells and that all cells come from other cells.
Cell Theory
The chemical activities of cells.
Cellular Metabolism
A membrane-enclosed sac occupying most of the interior of a mature
plant cell, having diverse roles in reproduction, growth, and development.
Central Vacuole
A structure in an animal cell composed of cylinders of microtubule triplets arranged in a 9 and 0 pattern. An animal usually has a centrosome with a pair of centrioles involved in cell division.
Centriole
An organelle found in plants and photosynthetic protists that absorbs sunlight and uses it to drive the synthesis of organic molecules (sugars) from carbon dioxide and water.
Chloroplasts
The complex of DNA and proteins that constitutes eukaryotic chromosomes; often used to refer to the diffuse, very extended form taken by chromosomes when a cell is not dividing.
Chromatin
A threadlike, gene-carrying structure found in the nucleus of a eukaryotic cell and most visible during mitosis and meiosis; also, the main gene-carrying structure of a prokaryotic cell. Chromosomes consist of chromatin, a combination of DNA and protein.
Chromosome
An infolding of the inner membrane of a mitochondrion in which is embedded the electron transport chain and the enzyme catalyzing the synthesis of ATP.
Crista
Everything inside a cell between the plasma membrane and the nucleus; consists of a semifluid medium and organelles.
Cytoplasm
A network of protein fibers in the cytoplasm of a eukaryotic cell; includes microfilaments, intermediate filaments, and microtubules.
Cytoskeleton
An instrument that focuses an electron beam through, or onto the surface of, a specimen. An electron microscope achieves a hundredfold greater resolution than a light microscope.
Electron Microscope (EM)
A network of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles.
Endomembrane System
An extensive membranous network in a eukaryotic cell, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free (smooth) regions.
Endoplasmic Reticulum
A process by which the mitochondria and chloroplasts of eukaryotic cells probably evolved from symbiotic associations between small prokaryotic cells living inside larger cells.
Endosymbiosis
A type of cell that has a membrane-enclosed nucleus and other membrane-enclosed organelles. All organisms except bacteria and archaea are composed of eukaryotic cells.
Eukaryotic Cell
A substance in which the cells of an animal tissue are embedded; consists of protein and polysaccharides.
Extracellular Matrix (ECM)
A long cellular appendage specialized for locomotion. The flagella of prokaryotes and eukaryotes differ in both structure and function. Like cilia, eukaryotic flagella have a 9 + 2 arrangement of microtubules covered by the cell’s plasma membrane.
Flagellum
A macromolecule consisting of one or more polypeptides linked to short chains of sugars.
Glycoprotein
An organelle in eukaryotic cells consisting of stacks of membranous sacs that modify, store, and ship products of the endoplasmic reticulum.
Golgi Apparatus
A stack of hollow disks formed of thylakoid membrane in a chloroplast. Grana are the sites where light energy is trapped by chlorophyll and converted to chemical energy during the light reactions of photosynthesis.
Granum
An intermediate-sized protein fiber that is one of the three main kinds of fibers making up the cytoskeleton of eukaryotic cells. Intermediate filaments are ropelike, made of fibrous proteins.
Intermediate Filament
An optical instrument with lenses that refract (bend) visible light to magnify images and project them into a viewer’s eye or onto photographic film.
Light Microscope
