chap 4 - flashcards - mader bio.txt

Muscle protein filament in a sarcomere; its movement shortens the sarcomere- yielding muscle contraction. Actin filaments play a role in the movement of the cell and its organelles.

A rod-shaped bacterium; also a genus of bacteria- Bacillus.

A cytoplasmic structure that is located at the base of�and may organize�cilia or flagella.

Gelatinous layer surrounding the cells of blue-green algae and certain bacteria.

Smallest unit that displays the properties of life; composed of organelle-containing cytoplasm surrounded by a plasma membrane.

In a prokaryotic cell- the portion composed of the plasma membrane- the cell wall- and the glycocalyx.

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.

Structure that surrounds a plant- protistan- fungal- or bacterial cell and maintains the cell's shape and rigidity.

In a plant cell- a large- fluid-filled sac that stores metabolites. During growth- it enlarges- forcing the primary cell wall to expand and the cell surface-area-to-volume ratio to increase.

Cell organelle- existing in pairs- that occurs in the centrosome and may help organize a mitotic spindle for chromosome movement during animal cell division.

Central microtubule organizing center of cells. In animal cells- it contains two centrioles.

Membrane bounded organelle in algae and land plants with chlorophyll-containing membranous thylakoids; where photosynthesis takes place.

Network of DNA strands and associated proteins observed within a nucleus that is not dividing.

Plastid in land plants responsible for orange- yellow- and red color of plants- including the autumn colors in leaves.

An observable structure that results when chromatin condenses and coils- each species has a particular number of chromosomes that is passed on to the next generation.

Short- hairlike projections from the plasma membrane- occurring usually in larger numbers (cilia).

A spherical-shaped bacterium.

In a bacterium- elongated- hollow appendage used to transfer DNA to other cells.

In magnification with a microscope- brightness differences between objects.

Short- fingerlike projections formed by the folding of the inner membrane of mitochondria.

Photosynthetic bacterium that contains chlorophyll and releases oxygen; formerly called a blue-green alga.

Contents of a cell between the nucleus (nucleoid) region of bacteria and the plasma membrane.

Internal framework of the cell- consisting of microtubules- actin filaments- and intermediate filaments.

Cellular system that consists of the nuclear envelope- endoplasmic reticulum- Golgi apparatus- and vesicles.

System of membranous saccules and channels in the cytoplasm- often with attached ribosomes.

Explanation of the evolution of eukaryotic organelles by phagocytosis of prokaryotes.

Type of cell that has a membrane bounded nucleus and membranous organelles; found in organisms within the domain Eukarya.

Small- bristlelike fiber on the surface of a bacterial cell- which attaches bacteria to a surface; also fingerlike extension from the oviduct near the ovary.

Long- slender extension used for locomotion by some bacteria- protozoans- and sperm.

Unit of heredity existing as alleles on the chromosomes; in diploid organisms- typically two alleles are inherited�one from each parent.

Gel-like coating outside the cell wall of a bacterium. If compact- it is called a capsule; if diffuse- it is called a slime layer.

Organelle consisting of sacs and vesicles that processes- packages- and distributes molecules about or from the cell.

Stack of chlorophyll-containing thylakoids in a chloroplast.

In a bacterium- stored nutrients for later use.

Ropelike assemblies of fibrous polypeptides in the cytoskeleton that provide support and strength to cells; so called because they are intermediate in size between actin filaments and microtubules.

Plastid- generally colorless- that synthesizes and stores starch and oils.

Membrane-bounded vesicle that contains hydrolytic enzymes for digesting macromolecules.

Using a microscope- enlarging an object for viewing.

Unstructured semifluid substance that fills the space between cells in connective tissues or inside organelles.

In a bacterium- plasma membrane that folds into the cytoplasm and increases surface area.

Small- cylindrical organelle composed of tubulin protein around an empty central core; present in the cytoplasm- centrioles- cilia- and flagella.

Membrane-bounded organelle in which ATP molecules are produced during the process of cellular respiration.

Protein that moves along either actin filaments or microtubules and translocates organelles.

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.

Opening in the nuclear envelope that permits the passage of proteins into the nucleus and ribosomal subunits out of the nucleus.

Region of prokaryotic cells where DNA is located; it is not bounded by a nuclear envelope.

Dark-staining- spherical body in the nucleus that produces ribosomal subunits.

Semifluid medium of the nucleus containing chromatin.

Small- often membranous structure in the cytoplasm having a specific structure and function.

Enzyme-filled vesicle in which fatty acids and amino acids are metabolized to hydrogen peroxide that is broken down to harmless products.

Membrane surrounding the cytoplasm that consists of a phospholipid bilayer with embedded proteins; functions to regulate the entrance and exit of molecules from cell.

Extrachromosomal ring of accessory DNA in the cytoplasm of bacteria.

Organelles of plants and algae that are bounded by a double membrane and contain internal membranes and/or vesicles (i.e.- chloroplasts- chromoplasts- leucoplasts).

String of ribosomes simultaneously translating regions of the same mRNA strand during protein synthesis.

Lacking a membrane-bounded nucleus and organelles; the cell type within the domains Bacteria and Archaea.

Cytoplasmic extension of amoeboid protists; used for locomotion and engulfing food.

Capability of a microscope to distinguish the separate parts of an object.

RNA and protein in two subunits; site of protein synthesis in the cytoplasm.

Membranous system of tubules- vesicles- and sacs in cells; has attached ribosomes.

Release of a substance by exocytosis from a cell that may be a gland or part of a gland.

Sequence of amino acids that binds with a SRP- causing a ribosome to bind to ER.

Membranous system of tubules- vesicles- and sacs in eukaryotic cells; lacks attached ribosomes.

Long- rod-shaped bacterium that is twisted into a rigid spiral; if the spiral is flexible rather than rigid- it is called a spirochete.

Long- rod-shaped bacterium that is twisted into a flexible spiral; if the spiral is rigid rather than flexible- it is called a spirillum.

Fluid within a chloroplast that contains enzymes involved in the synthesis of carbohydrates during photosynthesis.

Ratio of a cell's outside area to its internal volume.

Flattened sac within a granum whose membrane contains chlorophyll and where the light reactions of photosynthesis occur.

Membrane-bounded sac- larger than a vesicle; usually functions in storage and can contain a variety of substances. In plants- the central vacuole fills much of the interior of the cell.

Small- membrane-bounded sac that stores substances within a cell.