Chapter4Vocab

= ** Vocab Terms ** = ** Actin- one of the two protein filaments in a muscle cell that function in contraction ** ** Cell Wall- ** a ridged structure that surrounds the cell of plants, fungi, many protists, and most bacteria ** Chromatin- ** the DNA and proteins in the nucleus of a nondividing cell ** Chromosome ** - DNA and protein in a coiled, rod-shaped form that occurs during cell division ** Cilia- ** numerous, short hair like organelle that extends from a cell and functions in locomotion or in the movement of substances across the cell surface ** Cytoplasm- ** the region of a cell between the cell membrane and nucleus ** Cytoskeleton- ** a network of long protein strands located in the cytosol ** Cytosol - ** the gelatin like aqueous fluid that bathes the organelles on the inside of the cell membrane ** Endoplasmic Reticulum - ** a system of membranous tubules and sacs in eukaryotic cells that functions as a path along which molecules move from one part of the cell to another ** Flagella- a hairlike structure made up of microtubules that function in locomotion ** ** Fluid Mosaic Model ** - a model of cell membrane structure representing the dynamic nature of membrane lipids and proteins ** Golgi Apparatus- a system of membranes in eukaryotic cells that modifies proteins for export by the cell ** ** Integral Protein - a protein imbedded in the bilayer of the cell membrane ** ** Lysosome- ** an organelle containing digestive enzymes, existing primarily in animal cells ** Microtubule- a hollow tube of protein that constitutes the largest strand in the cytoskeleton ** ** Mitochondria- ** the organelle that is the site of aerobic respiration in eukaryotic cells ** Nuclear Envelope- ** the double membrane surronding the nucleus ** Nuclear Matrix- the nuclear skeleton, a shape-maintaining protein ** ** Nuclear Pores - ** small holes in the nuclear envelope through which substances pass between the nucleus and the cytoplasm ** Nucleolus- ** a structure in which ribosomes are synthesized and partially assembled; found in most nuclei ** Plastid - an organelle of plant cells that comtains strach, fats, or pigments ** ** Ribosme - an organelle that functions in the syntheis of proteins ** ** Rough ER- the portion of the endoplasmic reticulum that contains attached ribosomes ** ** Selectively Permeable Membrane-a membrane that keeps out some molecules but allows others to pass through ** ** Smooth ER- the portion of the endoplasmic reticulum that lacks attached ribosomes ** ** Spindle Fiber- ** one of the microtubules that extend across a dividing eukaryotic cell; assists in the movement of chromosomes ** Thylakoid- ** a flattened, membranous sac inside a chloroplast; contains most of the componenets involved in the light reactions of photosynthesis ** Vacuole- ** a fluid filled organelle that stores enzymes or metabolic wastes in a plant cell