Essentials of Biology 3rd Edition: Chapter 4

404259559	actin filament	Cytoskeletal filament of eukaryotic cells composed of the protein actin; also refers to the thin filaments of muscle cells.
404259560	adenosine triphosphate (ATP)	Nucleotide with three phosphate groups. The breakdown of ATP into ADP + p makes energy available for energy-requiring processes in cells.
404259561	adhesion junction	Junction between cells in which the adjacent plasma membranes do not touch but are held together by intercellular filaments attached to buttonlike thickenings.
404259562	capsule	Gelatinous layer surrounding the cells of green algae and certain bacteria.
404259563	cell	Smallest unit that displays the properties of life; composed of cytoplasm surrounded by a plasma membrane.
404259564	cell theory	One of the major theories of biology, which states that all organisms are made up of cells; cells are capable of self-reproduction and come only from preexisting cells.
404259565	cell wall	Structure that surrounds a plant, protistan, fungal, or bacterial cell and maintains the cell's shape and rigidity.
404259566	cellular respiration	Metabolic reactions that use the energy from carbohydrates, fatty acid, or amino acid breakdown to produce ATP molecules.
404259567	centriole	Cell organelle, existing in pairs, that occurs in the centrosome and may help organize a mitotic spindle for chromosome movement during animal cell division.
404259568	centrosome	Central microtubule organizing center of cells. In animal cells, it contains two centrioles.
404259569	chloroplast	Membrane-bounded organelle in algae and plants with chlorophyll-containing membranous thylakoids; where photosynthesis takes place.
404259570	chromatin	Network of fibrils consisting of DNA and associated proteins observed within a nucleus that is not dividing.
404259571	chromosome	Structure consisting of DNA complexed with proteins that transmits genetic information from the previous generation of cells and organisms to the next generation.
404259572	cilium (pl., cilia)	Short, hairlike projection from the plasma membrane, occurring usually in larger numbers.
404259573	conjugation pili	Tubular, rigid bacterial structures that enable the transmission of DNA from cell to cell.
404259574	cristae	Short, fingerlike projections formed by the folding of the inner membrane of mitochondria.
404259575	cytoplasm	Contents of a cell between the nucleus (nucleoid region of bacteria) and the plasma membrane.
404259576	cytoskeleton	Internal framework of the cell, consisting of microtubules, actin filaments, and intermediate filaments.
404259577	endomembrane system	Collection of membranous structures involved in transport within the cell.
404259578	endoplasmic reticulum (ER)	System of membranous saccules and channels in the cytoplasm, often with attached ribosomes.
404259579	eukaryotic cell	Type of cell that has a membrane-bounded nucleus and membranous organelles; found in organisms within the domain Eukarya.
404259580	extracellular matrix (ECM)	Meshwork of polysaccharides and proteins that provides support for an animal cell and affects its behavior.
404259581	fimbriae	In bacteria, small, bristlelike fibers on bacterial cell surface that enable bacteria to adhere to surfaces.
404259582	flagellum (pl., flagella)	Long, slender extension used for locomotion by some bacteria, protozoans, and sperm.
404259583	gap junction	Junction between cells formed by the joining of two adjacent plasma membranes; it lends strength and allows ions, sugars, and small molecules to pass between cells.
404259584	Golgi apparatus	Organelle consisting of saccules and vesicles that processes, packages, and distributes molecules about or from the cell.
404259585	granum	Stack of chlorophyll-containing thylakoids in a chloroplast.
404259586	lysosome	Membrane-bounded vesicle that contains hydrolytic enzymes for digesting macromolecules.
404259587	matrix	Unstructured semifluid substance that fills the space between cells in connective tissues or inside organelles.
404259588	microtubule	Small, cylindrical organelle composed of tubulin protein around an empty central core; present in the cytoplasm, centrioles, cilia, and flagella.
404259589	mitochondrion	Membrane-bounded organelle in which ATP molecules are produced during the process of cellular respiration.
404259590	motor protein	Proteins associated with the cytoskeleton that allow movement of transport vesicles and organelles.
404259591	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.
404259592	nuclear pore	Opening in the nuclear envelope that permits the passage of proteins into the nucleus and ribosomal subunits out of the nucleus.
404259593	nucleoid	Region of prokaryotic cells where DNA is located; it is not bounded by a nuclear envelope.
404259594	nucleolus	Dark-staining, spherical body in the nucleus that produces ribosomal subunits.
404259595	nucleus	Center of an atom, in which protons and neutrons are found; membrane-bounded organelle within a eukaryotic cell that contains chromosomes and controls the structure and function of the cell.
404259596	organelle	Small, often membranous structure in the cytoplasm having a specific structure and function.
404259597	plasma membrane	Membrane surrounding the cytoplasm that consists of a phospholipid bilayer with embedded proteins; functions to regulate the entrance and exit of molecules from a cell.
404259598	plasmodesmata	In plants, cytoplasmic strands that extend through pores in the cell wall and connect the cytoplasm of two adjacent cells.
404259599	polyribosome	String of ribosomes simultaneously translating regions of the same mRNA strand during protein synthesis.
404259600	prokaryotic cell	Lacking a membrane-bounded nucleus and organelles; the cell type within the domains Bacteria and Archaea.
404259601	ribosome	RNA and protein in two subunits; site of protein synthesis in the cytoplasm.
404259602	rough ER	Membranous system of tubules, vesicles, and sacs in cells; has attached ribosomes.
404259603	secretion	In the cell, release of a substance by exocytosis from a cell that may be a gland or part of a gland; in the urinary system, movement of certain molecules from blood into the distal tubule of a nephron so that they are added to urine.
404259604	smooth ER	Membranous system of tubules, vesicles, and sacs in eukaryotic cells; lacks attached ribosomes.
404259605	stroma	Fluid within a chloroplast that contains enzymes involved in the synthesis of carbohydrates during photosynthesis.
404259606	surface-area-to-volume ratio	A smaller value of this explains why smaller cells are more efficient.
404259607	thylakoid	Flattened sac within a granum whose membrane contains chlorophyll and where the light reactions of photosynthesis occur.
404259608	tight junction	Junction between cells when adjacent plasma membrane proteins join to form an impermeable barrier.
404259609	transport vesicles	Small membranous sacs that carry products between endomembrane system organelles and prevent the products from entering the cytoplasm.
404259610	vacuole	Membrane-bounded sac, larger than a vesicle; usually functions in storage and can contain a variety of substances. In plants, the it fills much of the interior of the cell.
404259611	vesicle	Small, membrane-bounded sac that stores substances within a cell.
404646038	fimbriae, conjugation pilius, flagellum, capsule, nucleoid, ribosome, plasma membrane, cell wall, cytoplasm
404646039	vesicle, centrioles, mitochondrion, rough ER, smooth ER, lysosome, golgi apparatus, nucleus, vesicle formation, ribosome, cytoplasm, polyribosome, microtubule, filament, nuclear pore, nuclear envelope, nucleolus, chromatin