BIOLOGY: CONCEPTS AND CONNECTIONS (Chapter 4) Flashcards

1028709897	Light microscope (LM)	Optical instrument with lenses that refract (bend) visible light to magnify images and project them into the viewer's eye or onto photographic film. These can be used to study live specimens, but they only magnify about a thousand times.
1028709898	Magnification	The increase in the apparent size of an object.
1028709899	Resolution	A measure of the clarity of an image OR the ability of an optical instrument to show objects as separate.
1028709900	Cell theory	The theory that all living things are composed of cells and that all cells come from other cells.
1028709901	Electron microscope (EM)	An instrument that focuses an electron beam through (or onto the surface of) a specimen. It has electromagnets as lenses and achieves a thousandfold greater resolution than a light microscope, but isn't that great for studying live specimens.
1028709902	Scanning electron microscope	Microscope that uses an electron beam to study (scan) the surface architecture of a cell (or other specimen). Produces images that look 3D.
1028709903	Transmission electron microscope	Microscope that uses an electron beam to study the internal structure of thinly sectioned specimens.
1028709904	Prokaryotic cell	A type of cell lacking a membrane-enclosed nucleus and other membrane-enclosed organelles. Found in bacteria and archaea.
1028709905	Eukaryotic cell	A type of cell that has a membrane-enclosed nucleus and other membrane-enclosed organelles. Found in protists, fungi, plants, and animals.
1028709906	Features of cells	- Bound by a plasma membrane - Genes made of DNA as hereditary material - Contain ribosomes
1028709907	Plasma membrane	A thin layer of lipids and proteins that sets cell off from surroundings and acts as a selective barrier to passage of ions and molecules into and out of the cell. Consists of a phospholipid bilayer in which are embedded molecules of protein and cholesterol.
1028709908	Ribosomes	Cell organelles consisting of RNA and protein organized into two subunits and functioning as the site of protein synthesis in cytoplasm. Constructed in the nucleolus.
1028709909	Nucleotide region	A region in a prokaryotic cell where the DNA is coiled.
1028709910	Cell wall	A protective layer external to the plasma membrane in plant cells, bacteria, fungi, and some protists. It protects and maintains the shape of the cell.
1028709911	Capsule	A sticky layer that surrounds the bacteria cell wall, protects the cell surface, and sometimes helps glue the cell to surfaces.
1028709912	Pilus	Short projections on the surface of a prokaryotic cell that helps it to attach to surfaces.
1028709913	Cytoplasm	Everything inside a eukaryotic cell between the plasma membrane and nucleus. It consists of a semifluid medium and organelles.
1028709914	Organelles	Structure with a specialized function in a cell.
1028709915	Cellular metabolism	The chemical activities of cells.
1028709916	Differences in eukaryotic plant cells	- Rigid, thick cell wall (like fungi and many protists) with cellulose. - Chloroplast (where photosynthesis occurs) - Central vacuole (a compartment that stores water and chemicals)
1028709917	Nucleus	The genetic control center of the eukaryotic cell. Contains DNA and controls the actions of the cell by directing protein synthesis.
1028709918	Chromatin	Combination of DNA and proteins that constitutes chromosomes. Sometimes used to refer to diffuse and very extended form taken by chromosomes when a cell isn't dividing.
1028709919	Chromosome	A threadlike, gene-carrying structure found in the nucleus of a eukaryotic cells and most visible during mitosis and meiosis. Also the main gene-carrying structure of prokaryotic cells.
1028709920	Nuclear envelope	A double membrane perforated with pores that encloses the nucleus.
1028709921	Nucleolus	A structure within a eukaryotic cell nucleus where ribosomal RNA is made and assembled with proteins to make ribosomal subunits. Consists of parts of chromatin DNA, RNA transcribed from that DNA, and proteins imported.
1028709922	Endomembrane system	A network of membranous organelles that partition the cytoplasm of a eukaryotic cells into functional compartments. Some membranes are physically connected, others are related by a transfer of membrane segments by tiny vesicles.
1028709923	Vesicles	Sacs made of membrane in the cytoplasm of a eukaryotic cell.
1028709924	Endoplasmic reticulum (ER)	Extensive membranous organelles in a eukaryotic cell, continuous with the outer nuclear membrane and composed of ribosome-studded (rough) and ribosome-free (smooth) regions.
1028709925	Smooth ER	A network of interconnected membranous tubules in the cytoplasm of a eukaryotic cell. Lacks ribosomes. The enzymes embedded in the membrane function in the synthesis of certain kinds of molecules, like lipids. Also serves as storage for calcium ions.
1028709926	Rough ER	A network of interconnected membranous sacs in the cytoplasm of a eukaryotic cell. Studded with ribosomes that make membrane and secretory proteins. Constructs membrane from phospholipids and proteins. They modify proteins that will be secreted or transported to other organelles.
1028709927	Secretory protein	A protein (like an antibody) that is secreted by a cell.
1028709928	Synthesis, modification, and packing of a secretory protein	1) As a polypeptide is synthesized by an attached ribosome, it passes into the ER, where it is folded into its 3D shape. 2) Short chains of sugars link to it, making it into a glycoprotein. 3) The ER packs it into a transport vesicle.
1028709929	Glycoprotein	A macromolecule consisting of one or more polypeptides linked to short chains of sugar.
1028709930	Transport vesicle	A tiny membranous sac in a cell's cytoplasm carrying molecules produced by the cell. Buds from the ER or Golgi eventually fuses with another membranous organelle or plasma membrane, releasing the contents.
1028709931	Golgi apparatus	An organelle in eukaryotic cells that consist of stacks of membranous sacs that modify, store, and ship ER products.
1028709932	Lysosome	A digestive organelle in eukaryotic cells that contains hydrolytic enzymes that digest the cell's food and wastes. The membrane encloses a compartment where digestive enzymes are provided with an acidic environment, safe from cytoplasm. These have digestive functions, they serve as recycling centers for cells, and play vital roles in embryonic development.
1028709933	Vacuoles	Membrane-enclosed sacs that are part of the endomembrane system of a eukaryotic cell. They have many diverse functions.
1028709934	Central vacuole	A membrane-enclosed sac occupying most of the interior of a mature plant cell. It has diverse roles in reproduction, growth, and development.
1028709935	Chloroplasts	Organelles found in plants and photosynthetic protists. Enclosed by two concentric membranes, chloroplasts absorb sunlight and use it to power the synthesis of organic food molecules (sugars).
1028709936	Stroma	A thick fluid found in the inner membrane of a chloroplast. This is where sugars are made by enzymes of the Calvin cycle.
1028709937	Granum	A stack of hollow disks formed of thylakoid membrane in a chloroplast. They are sites where light energy trapped by chlorophyll and converted to chemical energy during the light reactions of photosynthesis. The plural is "grana."
1028709938	Mitochondria	"Powerhouse" of the cell. Organelles in eukaryotic cells where cellular respiration occurs. Enclosed by two concentric membranes, they are where most of a cell's ATP is made. The singular is "mitochondrion."
1028709939	Mitochondrial matrix	The fluid in the inner membrane of a mitochondrion.
1028709940	Cristae	The folds in the intermembrane space of a mitochondrion. Enzyme molecules that make ATP are embedded in them.
1028709941	Cytoskeleton	Meshwork of fine fibers in the cytoplasm of a eukaryotic cell; includes microfilaments, intermediate filaments, and microtubules. It provides structural support and cell movement, as well as regulating activities.
1028709942	Microfilaments	The thinnest of the protein fibers in the cytoskeleton, they are solid helical rods composed of the globular protein actin. (Helps with moving, changing shape.)
1028709943	Intermediate filaments	The medium-sized, ropelike protein fibers of the cytoskeleton. (They reinforce shape and anchor organelles.)
1028709944	Microtubules	The thickest of the protein fibers in the cytoskeleton, they are straight, hollow tubes made of the globular protein tubulin. (Basis of structure and movement of cilia and flagella.)
1028709945	Cilia	Short appendages that propel some protists through water and move fluids across the surface of many tissue cells in animals with coordinated movements.
1028709946	Flagella	Long surface projections that propel cells with a whiplike motion.The singular is "flagellum."
1028709947	Basal body	A eukaryotic cell organelle consisting of a 9+0 arrangement of microtubule triplets; they may organize microtubule assembly of cilia/flagella. They are structurally similar to centrioles.
1028709948	Centriole	A structure in an animal cell composed of microtubule triplets in a 9+0 pattern, much like basal bodies. Animal cells have pairs of these within centrosomes.
1028709949	Plasmodesmata	Open channels in the cell walls of plants through which strands of cytoplasm connect from adjacent walls.
1028709950	Extracellular matrix	The substance in which the cells of an animal tissue are embedded; consists of proteins and polysaccharides. They help regulate cell behavior.
1028709951	Cell junctions	How adjacent cells in animal tissues are connected. 1) TIGHT JUNCTIONS (Form a leak-proof sheet.) 2) ANCHORING JUNCTIONS (Connects tissue cells to other tissue cells or the extracellular matrix and allows materials to pass from cell to cell.) 3) GAP JUNCTIONS (A channel through which water and other small molecules can pass through freely.)
1028709952	Micrograph	A photograph taken through a microscope.
1028709953	Resolution	A measure of the clarity of an image
1028709954	Prokaryotic flagellum	A long surface projection that propels a prokaryotic cell through its liquid environment; totally different from the flagellum of a eukaryotic cell.
1028709955	Lysosomal storage diseases	A hereditary disorder associated with abnormal lysosomes, where the sufferer is missing one of the lysosomal digestive enzymes.
1028709956	Intermembrane space	One of the two fluid-filled internal compartments of the mitochondrion, the narrow region between the inner and outer membranes.
1028709957	Dynein arm	A protein extension from a microtubule doublet in a cilium or flagellum; involved in energy conversions that drive the bending of cilia and flagella.
1028709958	Tight junction	A junction that binds tissue cells together in a leakproof sheet.
1028709959	Anchoring junction	A junction that connects tissue cells to each other (or to an extracellular matrix) and allows materials to pass from cell to cell.
1028709960	Communication junction	A channel between adjacent tissue cells through which water and other molecules pass freely.