Mader 04 Vocabulary

Front 1

actin filament

Back 1

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

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apoptosis

Back 2

Programmed cell death involving a cascade of specific cellular events leading to death and destruction of the cell

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bacillus

Back 3

A rod-shaped bacterium

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basal body

Back 4

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

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capsule

Back 5

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

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cell

Back 6

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

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cell envelope (of prokaryotes)

Back 7

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

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cell theory

Back 8

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.

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cell wall

Back 9

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

Front 10

central vacuole (of plant cell)

Back 10

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.

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centriole

Back 11

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

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centrosome

Back 12

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

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chloroplast

Back 13

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

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chromatin

Back 14

network of fibrils consisting of DNA and associated proteins observed within a nucleus that is not dividing.

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chromoplast

Back 15

Organelles that contain pigments that result in a yellow, orange, or red color. Chromoplasts are responsible for the color of autumn leaves, fruits, carrots, and some flowers.

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chromosome

Back 16

Coiled, rodlike structures of condensed chromatin.

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cilium

Back 17

Short, hairlike projection from the plasma membrane, occurring usually in larger numbers (cilia)

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coccus

Back 18

A spherical-shaped bacterium

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cristae

Back 19

Short, fingerlike projections formed by the folding of the inner membrane of mitochondria

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cyanobacteria

Back 20

Photosynthetic bacteria that contain chlorophyll and release oxygen; formerly called blue-green algae.

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cytoplasm

Back 21

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

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cytoskeleton

Back 22

Internal framework of the cell, consisting of microtubules, actin filaments, and intermediate filaments

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endomembrane system

Back 23

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

Front 24

endoplasmic reticulum (ER)

Back 24

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

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eukaryotic cell

Back 25

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

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fimbriae

Back 26

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.

Front 27

flagellum (pl., flagella)

Back 27

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

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glycocalyx

Back 28

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.

Front 29

Golgi apparatus

Back 29

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

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granum

Back 30

Stack of chlorophyll-containing thylakoids in a chloroplast.

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inclusion body

Back 31

In a bacterium, stored nutrients for later use.

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intermediate filament

Back 32

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.

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leucoplast

Back 33

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

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lysosome

Back 34

Membrane-bounded vesicle that contains hydrolytic enzymes for digesting macromolecules

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matrix

Back 35

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

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mesosome

Back 36

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

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microtubule

Back 37

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

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mitochondrion

Back 38

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

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motor molecule

Back 39

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

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nuclear envelope

Back 40

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.

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nuclear pore

Back 41

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

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nucleoid

Back 42

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

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nucleolus

Back 43

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

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nucleoplasm

Back 44

Semifluid medium of the nucleus containing chromatin

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nucleus

Back 45

Membrane-bounded organelle within a eukaryotic cell that contains chromosomes and controls the structure and function of the cell.

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organelle

Back 46

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

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peroxisome

Back 47

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

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plasma membrane

Back 48

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

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plasmid

Back 49

Self-duplicating ring of accessory DNA in the cytoplasm of bacteria.

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plastid

Back 50

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

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polyribosome

Back 51

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

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prokaryotic cell

Back 52

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

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pseudopod

Back 53

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

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ribosome

Back 54

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

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rough ER

Back 55

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

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secretion

Back 56

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

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sex pili

Back 57

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

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smooth ER

Back 58

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

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spirillum

Back 59

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

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spirochete

Back 60

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

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stroma

Back 61

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

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surface-area-to-volume ratio

Back 62

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

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thylakoid

Back 63

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

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vacuole

Back 64

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.

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vesicle

Back 65

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