[Biology] Ch.1: The Cell

Question 1

what is a benefit of membrane bound organelles

Answer 1

compartmentalization of function

Question 2

what does the nucleus contain

Answer 2

all of the genetic material necessary for replication of the cell

Question 3

the nuclear membrane/envelope is a [ 1 ] that [ 2 ]

Answer 3

1) double membrane 2) maintains a nuclear environment separate and distinct from the cytoplasm

Question 4

what do nuclear pores do

Answer 4

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

Question 5

in the nucleus, linear DNA is organized around [ 1 ] and then further wound to form [ 2 ]

Answer 5

1) histones 2) chromosomes

Question 6

the location of DNA in the nucleus allows for compartmentalization of [ 1 ] from [ 2 ]

Answer 6

1) DNA transcription 2) RNA translation

Question 7

what is the nucleolus

Answer 7

a subsection of the nucleus where ribosomal RNA is synthesized

Question 8

contrast the outer and inner membrane of the mitochondria

Answer 8

• outer membrane = barrier between the cytosol and inner environment
• inner membrane = contains the molecules and enzymes necessary for the electron transport chain

Question 9

what are cristae

Answer 9

infoldings in the mitochondrial inner membrane

Question 10

what is the benefit of having cristae

Answer 10

they increase the surface area available for the electron transport chain enzymes

Question 11

contrast the locations of the inter membrane space and mitochondrial matrix

Answer 11

• intermembrane space = located between the inner and outer membranes
• mitochondrial matrix = space inside the inner membrane

Question 12

the pumping of protons from the [ 1 ] to the [ 2 ] establishes the proton-motive force. protons flow through [ 3 ] to generate ATP using [ 4 ]

Answer 12

1) mitochondrial matrix 2) intermembrane space 3) ATP synthase 4) oxidative phosphorylation

Question 13

how are mitochondria different from other parts of the cell

Answer 13

they are semi autonomous, contain some of their own genes, and replicate independently of the nucleus

Question 14

how do mitochondria replicate

Answer 14

using binary fission

Question 15

how do mitochondria contribute to apoptosis

Answer 15

release of enzymes from the electron transport chain

Question 16

what are lysosomes

Answer 16

membrane- bound structures containing hydrolytic enzymes capable of breaking down many different substrates, including substances ingested by endocytosis and cellular waste products

Question 17

what happens during autolysis

Answer 17

lysosomes release their enzymes into the cell

Question 18

what is the endoplasmic reticulum

Answer 18

a series of interconnected membranes that are actually contiguous with the nuclear envelope

Question 19

what’s the benefit of the rough ER being studded with ribosomes

Answer 19

proteins destined for secretion an be secreted directly into its lumen

Question 20

what are the primary functions of the smooth ER

Answer 20

lipid synthesis and detoxification of certain drugs and poisons

Question 21

how are the smooth and rough ER related

Answer 21

the smooth ER will transport proteins from the rough ER to the golgi apparatus

Question 22

what happens to cellular products once in the golgi apparatus

Answer 22

they are modified by the addition of various groups (including carbohydrates, sulfates, and phosphates)

Question 23

how are products in the golgi modified to direct them to correct cellular locations

Answer 23

using the introduction of signal sequences

Question 24

peroxisomes contain [ 1 ]

Answer 24

hydrogen peroxide

Question 25

what is the primary function of peroxisomes

Answer 25

the breakdown of very long fatty acid chains via beta- oxidation

Question 26

peroxisomes also participate in [ 1 ] and contain some of the enzymes involved in the [ 2 ] pathway

Answer 26

1) phospholipid synthesis 2) pentose phosphate

Question 27

the cytoskeleton provides [ 1 ] to the cell and helps it maintain its [ 2 ]

Answer 27

1) structure 2) shape

Question 28

True or False: the cytoskeleton is involved in the transport of materials around the cell

Answer 28

true

Question 29

what are the three components of the cytoskeleton

Answer 29

microtubules, microfilaments, and intermediate filament proteins

Question 30

what are microfilaments made up of

Answer 30

solid polymerized rods of actin

Question 31

actin filaments are resistant to both [ 1 ] and [ 2 ]

Answer 31

1) compression 2) fracture

Question 32

describe cytokinesis

Answer 32

the division of materials between daughter cells

Question 33

True of False: microfilaments form the cleavage furrow (ring at the site of division between two daughter cells

Answer 33

true

Question 34

what are microtubules

Answer 34

hollow polymers of tubulin proteins

Question 35

microtubules form the primary pathways along which motor proteins like [ 1 ] and [ 2 ] carry vesicles

Answer 35

1) kinesin and 2) dynein

Question 36

what is the difference between cilia and flagella

Answer 36

- cilia = primarily involved in movement of materials along cell surface - flagella = involved in movement of the cell itself

Question 37

what are centrioles

Answer 37

the organizing centers for microtubules

Question 38

what are intermediate filament proteins involved in

Answer 38

cell-cell adhesion and maintenance of overall integrity of the cytoskeleton

Question 39

intermediate filament proteins are resistant to [ 1 ]

Answer 39

strain from tension

Question 40

what is the relationship between intermediate filament proteins and other organelles

Answer 40

intermediate filament proteins help anchor organelles

Question 41

True or False: the identity of intermediate filament proteins within a cell is random

Answer 41

False. The identity of intermediate filament proteins within a cell is specific to the cell and tissue type

Question 42

what are the four tissue types

Answer 42

epithelial, connective, muscle, and nervous tissue

Question 43

where is epithelial tissue located

Answer 43

it covers the body and lines its cavities

Question 44

what is the relationship between epithelial tissue and pathogen invasion and desiccation

Answer 44

epithelial tissue provides a mean of protection against pathogen invasion and desiccation

Question 45

how do epithelial cells remain one cohesive unit

Answer 45

they are tightly joined to each other and an underlying layer of connective tissue

Question 46

in most organs, epithelial cells constitutes the parenchyma ([ 1 ])

Answer 46

the functional parts of the organ

Question 47

explain the polarity of epithelial cells

Answer 47

- one side faces the lumen (hollow inside of an organ/ tube) OR the outside world - one side interacts with underlying blood vessels and structural cells

Question 48

what are the three classifications of epithelial cells based on layering

Answer 48

- simple epithelia (one layer of cells) - stratified epithelia (multiple layers of cells) - pseudostratified epithelia (look like multiple layers of cells due to cell height but it's only one layer)

Question 49

what's the difference between cuboidal, columnar, and squamous cells

Answer 49

- cuboidal = cube shaped - columnar = long and thin - squamous = flat and scale like

Question 50

what is the stroma

Answer 50

support structure of an organ

Question 51

most cells in connective tissues produce and secrete materials such as collagen and elastin to form [ 1 ]

Answer 51

the extracellular matrix

Question 52

what is the difference between mutualistic symbiotes and pathogens/ parasites

Answer 52

- mutualistic symbiotes = both humans and the bacteria benefit from the relationship - pathogens/parasites = no advantage or benefit to the host and can cause disease

Question 53

what is the difference in shape between cocci, bacilli, and spirilli bacteria

Answer 53

- cocci = spherical - bacilli = rod-shaped - spirilli = spiral shaped

Question 54

what are obligate aerobes

Answer 54

bacteria that require oxygen for metabolism

Question 55

what are anaerobes

Answer 55

bacteria that use fermentation or some other form of cellular metabolism that does not require oxygen

Question 56

why can't obligate anaerobes survive in an oxygen-containing environment

Answer 56

the presence of oxygen leads to the production of reactive oxygen-containing radicals

Question 57

what's the difference between facultative anaerobes and aerotolerant anaerobes

Answer 57

- facultative = can toggle between aerobic and anaerobic metabolism depending on the presence of oxygen - aerotolerant = unable to use oxygen for metabolism but not harmed by its presence in the environment

Question 58

what's different between gram positive and negative bacteria

Answer 58

gram negative has much more peptidoglycan in the cell wall and lipoteichoic acid

Question 59

what are plasmids

Answer 59

small circular structures containing DNA acquired from external sources

Question 60

how do prokaryotes reproduce

Answer 60

asexual reproduction in the form of binary fission

Question 61

what is bacterial transformation

Answer 61

the integration of foreign genetic material into the host genome

Question 62

what is bacterial conjugation

Answer 62

the bacterial form of mating

Question 63

what is the F factor

Answer 63

the fertility factor that enables cells to transfer copies of their plasmids to other bacteria

Question 64

what is transduction

Answer 64

the only genetic recombination process that requires a vector (a virus) to carry genetic material from one bacteria to another

Question 65

what are transposons

Answer 65

genetic elements capable of inserting removing themselves from the genome

Question 66

what are the four stages of the bacterial growth curve

Answer 66

the lag phase, the exponential phase, stationary phase, the death phase

Question 67

what are viruses composed of

Answer 67

genetic material, a protein coat, and sometimes an envelope containing lipids

Question 68

why are viruses considered obligate parasites

Answer 68

they cannot reproduce independently

Question 69

what's the difference between single stranded positive sense and negative sense RNA viruses

Answer 69

- positive sense = the genome can be directly translated to functional proteins by the ribosome of the host cell (like mRNA) - negative sense = require synthesis of RNA strand complementary to the negative sense RNA strand which can then be used as a template for protein synthesis

Question 70

negative-sense RNA viruses must carry RNA replicase to ensure [ 1 ]

Answer 70

the complementary strand is synthesized

Question 71

what are retroviruses

Answer 71

Single-stranded RNA viruses carrying reverse transcriptase which synthesizes DNA from single-stranded RNA

Question 72

how do retroviruses evade the host immune system

Answer 72

the viral DNA is incorporated into the host cell's DNA and is transcribed as if it were the host's own DNA

Question 73

can viruses infect any kind of cell; why or why not

Answer 73

no. they can only infect a specific cell type because they have to bind to specific receptors on a host cell to infect it

Question 74

what is the lytic vs lysogenic cycle

Answer 74

- lytic = virus replicates until the cell lyses | - lysogenic = viral DNA becomes part of the host's DNA and replicates accordingly