Biology Chapter 4 - Cell Structure

Question 1

Cell wall

Answer 1

rigid cell covering comprised of various molecules that protects the cell, provides structural support, and gives shape to the cell

Question 2

central vacuole

Answer 2

large plant cell organelle that regulates the cell’s storage compartment, holds water, and plays a significant role in cell growth as the site of macromolecule degradation

Question 3

Centrosome

Answer 3

region in animal cells made of two centrioles that serves as an organizing center for microtubules

Question 4

chlorophyll

Answer 4

green pigment that captures the light energy that drives the light reactions of photosynthesis

Question 5

chloroplast

Answer 5

plant cell organelle taht carries out photosynthesis

Question 6

chromatin

Answer 6

protein-DNA complex that serves as the chromosomes’ building material

Question 7

chromosome

Answer 7

structure within the nucleus that comprises chromatin that contains DNA, the hereditary material

Question 8

cilium

Answer 8

(Plural = cilia) short, hair-like structure that extends from the plasma membrane in large numbers and functions to move an entire cell or move substances along the cell’s outer surface

Question 9

cytoplasm

Answer 9

entire region between the plasma membrane and the nuclear envelope, consisting of organelles suspended in gel-like cytosol, the cytoskeleton, and various chemicals

Question 10

cytoskeleton

Answer 10

protein fiber network that collectively maintains the cell’s shape, secures some organelles in specific positions, allows cytoplasm and vesicles to move within the cell , and enables unicellular organisms to move independently

Question 11

cytosol

Answer 11

the cytoplasm’s gel-like material in which cell structures are suspended

Question 12

desmosome

Answer 12

linkages between adjacent epithelial cells that form when cadherins in the plasma membrane attach to intermediate filaments

Question 13

electron microscope

Answer 13

an instrument that magnifies an object using an electron beam that passes and bends through a lens system to visualize a specimen

Question 14

endomembrane system

Answer 14

group of organelles and membranes in eukaryotic cells that work together modifying, packaging, and transporting lipids and proteins

Question 15

endoplasmic reticulum (ER)

Answer 15

series of interconnected membranous structures within eukaryotic cells that collectively modify proteins and synthesize lipids

Question 16

Eukaryotic cell

Answer 16

cell that has a membrane-bound nucleus and several other membrane-bound compartments or sacs

Question 17

extracellular matrix

Answer 17

material secreted from animal or fungal cells that provide mechanical protection and anchoring for the cells in the tissues

Question 18

flagellum

Answer 18

(Plural = flagella) long, hair-like structure that extends from the plasma membrane and moves the cell

Question 19

gap junction

Answer 19

channel between two adjacent animal cells that allows ions, nutrients, and low molecular weight substances to pass between cells, enabling the cells to communicate

Question 20

Golgi apparatus

Answer 20

eukaryotic organelle comprised of series of stacked membranes that sorts, tags, and packages lipids and proteins for distribution

Question 21

Intermediate Filament

Answer 21

cytoskeletal component, comprised of several fibrous protein intertwined strands, that bears tension, supports cell-cell junctions, and anchors cells to extracellular structures

Question 22

lysosome

Answer 22

organelle in an animal cell that functions as the cell’s digestive component; it breaks down proteins, polysaccharides, lipids, nucleic acids, and even worn-out organelles

Question 23

microfilament

Answer 23

the cytoskeleton system’s narrowest element; it provides rigidity and shape to the cell and enables cellular movements

Question 24

Microtubules

Answer 24

the cytoskeleton system’s widest element; it helps the cell resist compression, provides a track along which vesicles move through the cell, pulls replicated chromosomes to opposite ends of a dividing cell, and is the structural element of centrioles, flagella, and cilia

Question 25

mitochrondria

Answer 25

(Singular - mitochondrion) cellular organelles responsible for carrying out cellular respiration, resulting in producing ATP, the cell’s main energy-carrying molecule

Question 26

Nucleoid

Answer 26

central part of a prokaryotic cell’s central part where the chromosome is located

Question 27

nucleolus

Answer 27

darkly staining body within the nucleus that is responsible for assembling ribosome subunits

Question 28

nucleoplasm

Answer 28

semi-solid fluid inside the nucleus that contains the chromatin and nucleolus

Question 29

tight junction

Answer 29

protein adherence that creates a firm seal between two adjacent animal cells

Question 30

plasmodesma

Answer 30

(Plural - plasmodesmata) channel that passes between adjacent plant cells’ cell walls, connects their cytoplasm, and allows transporting of materials from cell to cell

Question 31

peroxisome

Answer 31

small, round organelle that contains hydrogen peroxide, oxidizes fatty acids and amino acids, and detoxifies many poisons

Question 32

plasma membrane

Answer 32

phospholipid bilayer with embedded (integral) or attached (peripheral) proteins, and separates the cell’s internal content from its surrounding environment

Question 32

prokartyote

Answer 32

unicellular organism that lacks a nucleus or any other membrane-bound organelle

Question 33

ribosome

Answer 33

cellular structure that carries out protein synthesis

Question 34

rough endoplasmic reticulum (RER)

Answer 34

region of the endoplasmic reticulum that is studded with ribosomes and engages in protein modification and phospholipid synthesis

Question 35

smooth endoplasmic reticulum (SER)

Answer 35

region of the endoplasmic reticulum that has few or no ribosomes on its cytoplasmic surface and synthesizes carbohydrates, lipids, and steroid hormones; detoxifies certain chemicals (like pesticides, preservatives, medications, and environmental pollutants), and stores calcium ions

Question 36

unified cell theory

Answer 36

a biological concept that states that one or more cells comprise all organisms; the cell is the basic unit of life; and new cells arise from existing cells

Question 37

vacuole

Answer 37

membrane-bound sac, somewhat larger than a vesicle, which functions in cellular storage and transport

Question 38

vesicle

Answer 38

small, membrane-bound sac that functions in cellular storage and transport; its membrane is capable of fusing with the plasma membrane and the membranes of the endoplasmic reticulum and Golgi apparatus