Chapter 4 Flashcards
(54 cards)
Plasma Membrane
Outer surface that regulates entrance and exit of molecules
Cytoskeleton
Maintains cell shape and assists movement of cell parts. Internal framework of the cell, consisting of microtubules, actin filaments, and intermediate filaments
Microtubules
Protein cylinders that move organelles
Intermediate Fillaments
Protein fibers that provide stability or shape
Actin Filaments
Protein fibers that play a role in cell division and shape
Centrioles
Short cylinders of microtubules. Not found in plant cells
Centrosome
Microtubule organizing center that contains a pair of centrioles
Vesicle
Small membrane bound sac that stores and transports substances
Lysosome
Vesicle that digests macromolecules and even cell parts. Not commonly found in plant cells
Golgi apparatus
Processes, packages, and secretes modified proteins
Mitochondrion
Organelle that carries out cellular respiration producing ATP molecules
Polyribosome
String of ribosomes simultaneously translating regions of the same mRNA strand during protein synthesis
Ribosome
Particles that carry out protein synthesis; composed of proteins and ribosomal RNA (rRNA)
Peroxisome
Vesicle that is involved in fatty acid metabolism
Smooth ER
Lacks ribosomes, synthesizes lipid molecules
Rough ER
Studded with ribosomes that synthesize proteins. Membranous system of tubules, vesicles, and sacs in cells.
Endoplasmic Reticulum (ER)
System of membraneous saccules and channels int the cytoplasm. Often with attached ribosomes. Protein and lipid metabolism
Nucleolus
Region that produces subunits of ribosomes. Dark- staining spherical body in the nucleus
Chromatin
Network of DNA strands and associated proteins observed within a nucleus of a cell. Diffuse threads containing DNA and protein
Nuclear Envelope
Double membrane that surrounds the nucleus in eukaryotic cells and is connected to the endoplasmic reticulum. Has pores that allow substances to pass between the nucleus and the cytoplasm
Nucleus
Command center of cell. Membrane-bound organelle within a eukaryotic cell that contains chromosomes and controls the structure and function of the cell
Cell theory
- all organisms are composed of cells
- cells are the basic unit of structure and function in organisms
- cells come only from preexisting cells because cells are self-reproducing
Prokaryotic Cells
Cells without a membrane-bound nucleus
Eukaryotic Cells
Cells that posses a nucleus.