Chapter 1: The Cell

Question 1

Cell Theory

Answer 1

all living things are composed of cells
the cell is the basic functional unit of life
cells arise only from preexisting cells
cells carry genetic information in the form of DNA which is passed from parent to daughter cell

Question 2

cell membranes

Answer 2

made of a phospholipid bilayer; surface is hydrophilic and inner portion is hydrophobic; highly selective barrier

Question 3

nucleus

Answer 3

contains all genetic material necessary for replication

surrounded by the nuclear membrane/envelope

Question 4

nuclear membrane/envelope

Answer 4

double membrane surrounding the nucleus that maintains a separate nuclear environment

Question 5

nuclear pores

Answer 5

allow for selective two-way exchange of material between the cytoplasm and the nucleus

Question 6

nucleolus

Answer 6

subsection of the nucleus where rRNA is synthesized

Question 7

mitochondria

Answer 7

contains an outer and inner membrane; powerhouse of the cell; are semiautonomous (have their own genes and replicate independently); capable of killing the cells through release of the ETC enzymes triggering apoptosis

Question 8

outer mitochondrial membrane

Answer 8

barrier between the cytosol and the inner mitochondria

Question 9

inner mitochondrial membrane

Answer 9

has foldings called cristae and contains the molecules and enzymes necessary for the ETC

Question 10

cristae

Answer 10

infoldings in the inner mitochondrial membrane that increase the surface area available for the ETC enzymes

Question 11

intermembrane space

Answer 11

space between the inner and outer mitochondrial membranes

Question 12

mitochondrial matrix

Answer 12

space inside the inner membrane

Question 13

cytoplasmic or extranuclear inheritence

Answer 13

transmission of genetic material independent of the nucleus

Question 14

lysosomes

Answer 14

membrane-bound structures containing hydrolytic enzymes; sequesters enzymes to prevent damage to the cell; release causes autolysis

Question 15

endoplasmic reticulum

Answer 15

series of interconnected membranes that are contiguous with the nuclear envelope; membrane has numerous invaginations; can either be rough (have ribosomes) or smooth

Question 16

rough endoplasmic reticulum

Answer 16

studded with ribosomes; translation of proteins destined for secretion directly into the lumen

Question 17

smooth endoplasmic reticulum

Answer 17

lacks ribosomes; mostly used for lipid synthesis and detoxification of drugs and poisons; transports proteins from the RER to the Golgi apparatus

Question 18

Golgi apparatus

Answer 18

consists of stacked membrane-bound vesicles; receives materials from the ER in vesicles; modifies cellular products and packages them into vesicles for delivery to a specific cellular location

Question 19

exocytosis

Answer 19

secretory vesicles merge with cell membrane and are secreted

Question 20

peroxisomes

Answer 20

contain hydrogen peroxide; break down long fatty acid chains via beta oxidation; synthesis of phospholipids; contain enzymes in the pentose phosphate pathway

Question 21

cytoskeleton

Answer 21

provides structure to the cell and helps it maintain its shape; conduit for transport of materials around the cell; composed of microfilaments, microtubules and intermediate filaments

Question 22

microfilaments

Answer 22

made up of solid polymerized rods of actin organized into bundles and networks; resistant to compression and fracture; protect the cell; can be use ATP to generate force for movement by interacting with myosin

Question 23

cytokinesis

Answer 23

division of materials into daughter cells; cleavage furrow is made up of microfilaments

Question 24

microtubules

Answer 24

hollow polymers of tubular proteins; radiate throughout the cell; pathway for motor proteins like kinesin and dynein; make up cilia and flagella

Question 25

cilia

Answer 25

projections from cells that are involved in the movement of materials along the surface of the cell

Question 26

flagella

Answer 26

involved in the movement of the cell

Question 27

intermediate filaments

Answer 27

group of filamentous proteins including keratin, desmin, vimentin and lamins; involved in cell-cell adhesion or maintenance of the cytoskeleton; make the cell rigid and anchor organelles

Question 28

four types of tissue

Answer 28

epithelial, connective, muscle, nerve

Question 29

epithelial tissue

Answer 29

covers the body and lines cavities; protects agains pathogen invasion; can be involved in absorption, secretion and sensation; cells are tightly joined together to the basement membrane; highly diverse; often polarized

Question 30

simple epithelia

Answer 30

one layer of cells

Question 31

stratified epithelia

Answer 31

multiple layers

Question 32

pseudostratisfied epithelia

Answer 32

appear to have multiple layers due to difference in height but are one layer

Question 33

cuboidal

Answer 33

cube-shaped cells

Question 34

columnar

Answer 34

long and thin cells

Question 35

squamous

Answer 35

flat and scale-like cells

Question 36

connective tissue

Answer 36

supports the body; provides a framework for epithelial cells; bone, cartilage, tendons, ligaments, adipose tissue, blood; produce and secrete materials that make up the extracellular matrix

Question 37

nucleoid region

Answer 37

area of a prokaryotic cell where DNA is concentrated