Deck 3: Bacteria and Archaea

Question 1

The genus of bacteria that undergoes cell division in random planes, forming grapelike clusters of round bacteria, are the __________.

Answer 1

staphylococci

Question 2

Sterol-like molecules called hopanoids are thought to be important for the structural integrity of many bacteria because of their suspected role in membrane stabilization.

Answer 2

True

Question 3

Bacterial cells that are variable in shape are called

A) vibrio.
B) pleomorphic.
C) coccobacilli.
D) hyphal.

Answer 3

B

Question 4

Actinomycetes form long filaments called ___________.

Question 5

Which of the following is/are true of capsules?

A) They help bacteria escape phagocytosis by host cells.
B) They retain water and help prevent desiccation of the bacteria.
C) They prevent entry of many bacterial viruses.
D) all of the choices

Question 6

Square planar arrangement of cells that forms when round bacteria remain attached to each other during reproduction are called

A) streptococci.
B) staphylococci.
C) tetrads.
D) sarcinae.

Question 7

Proteins that are loosely associated with the cytoplasmic membrane are called __________ proteins.

A) peripheral
B) integral
C) external
D) internal

Question 8

The concept of a prokaryote was first fully outlined in 1962 by

A) Watson and Crick
B) Stanier and Van Niel
C) Hersey and Chase
D) Gilbert and Cech

Question 9

A branched network of hyphae formed by the Actinomycetes is called a __________.

Question 10

The term used to describe bacteria that have a spherical shape is

A) coccus.
B) bacillus.
C) vibrio.
D) coccobacillus.

Question 11

The term used to describe bacteria that are intermediate in shape between spherical and rod-shaped is

A) cocci.
B) bacilli.
C) vibrio.
D) coccobacilli.

Question 12

The cytoplasmic membrane of bacteria

A) retains the cytoplasm and its contents.
B) acts as a selectively permeable barrier, allowing some molecules to pass while preventing the movement of others.
C) is the major site of ATP synthesis in aerobes.
D) all of the choices

Question 13

Rigid bacteria with a helical cell shape are called

A) vibrios.
B) spirilla.
C) spirochetes.
D) coccobacilli.

Question 14

Flexible bacteria with a helical shape are called

A) vibrios.
B) spirilla.
C) spirochetes.
D) coccobacilli.

Question 15

The term used to describe bacteria that are shaped like curved rods is

A) coccus.
B) bacillus.
C) vibrio.
D) coccobacillus.

Question 16

The lipopolysaccharide (LPS) that is found in the outer membrane of gram-negative bacteria is also known as

A) exotoxin.
B) teichoic acid.
C) murein.
D) endotoxin.

Question 17

Bacteria that do not have a fixed shape are said to be __________.

Question 18

The term used to describe bacteria that are rod shaped is

A) coccus.
B) bacillus.
C) vibrio.
D) coccobacillus.

Question 19

Shrinkage of the plasma membrane away from the cell wall when the bacterium is placed in a hypertonic environment is called

A) osmolysis.
B) plasmolysis.
C) hydrolysis.
D) hypertonolysis.

Question 20

Proteins that are embedded within the cytoplasmic membrane and not easily extracted are called __________ proteins.

A) peripheral
B) integral
C) external
D) internal

Question 21

Although penicillin inhibits peptidoglycan synthesis, bacterial cells will continue to grow normally in the presence of penicillin in a(n) __________ environment.

A) hypotonic
B) isotonic
C) hypertonic
D) nonpolar

Question 22

When the cell wall is removed from a Gram-negative bacterium without removing the outer membrane, the resulting form is called a(n) __________.

Question 23

Cell walls of most Archaea and bacteria contain peptidoglycan.

Question 24

All of the following statements about the periplasmic space are true except:

A) It is found only in gram-positive bacteria.
B) It is located between the plasma membrane and outer membrane of gram-negative bacteria.
C) It contains hydrolytic enzymes and binding proteins involved in nutrient acquisition.
D) All of the above are true.

Question 25

_______ is a peptidoglycan-like molecule found in the cell walls of some archaea.

Question 26

Lipids with polar and nonpolar ends are said to be

A) amphipathic.
B) amphibolic.
C) bilateral.
D) none of the choices.

Question 27

The most widely accepted current model for membrane structures is called the __________ model.

Question 28

A __________ layer consists of diffuse unorganized polysaccharide material that lies outside the cell wall and is easily removed.

Question 29

Gram-positive bacteria have a thinner layer of peptidoglycan than gram-negative bacteria.

Question 30

A feature unique to some archaeal plasma membranes is that they may

A) consist of a lipid bilayer that lacks integral membrane proteins.
B) consist of a lipid bilayer with embedded proteins.
C) contain sterols such as cholesterol.
D) consist of a lipid monolayer.

Question 31

The cell membrane is a rigid structure that provides bacteria with their characteristic shapes.

Question 32

Sortase is a protein enzyme of bacteria that

A) plays a key role in directing proteins to the periplasm.
B) catalyzes covalent attachment of some surface proteins to peptidoglycan.
C) directs secretion of proteins across the outer membrane.
D) functions by transporting flagellum proteins to their extracellular site of assembly.

Question 33

A __________ is a polysaccharide layer that lies outside the cell wall and is not easily removed.

Question 34

The layers of peptidoglycan of the bacterial cell wall can be cross-linked by peptide intrabridges or by direct cross-linking.

Question 35

Bacteria growing at lower temperatures have more saturated fatty acids in their membranes.

Question 36

Enzymes that are secreted out of the cell to aid in the acquisition and digestion of environmental nutrients are called __________.

Question 37

Which of the following protects bacteria from lysis in dilute solutions and helps to determine their cellular morphology or shape?

A) plasma membrane
B) peptidoglycan
C) capsule
D) gas vacuoles

Question 38

Molecules or regions of molecules that readily interact with water are said to be __________, whereas molecules or regions of molecules that are insoluble in water or do not readily interact with water are said to be __________.

Question 39

A(n) __________ layer is a layer of protein or glycoprotein that exhibits a pattern resembling floor tiles.

Question 40

Gram-positive bacteria have a structurally and chemically more complex cell wall than gram-negative bacteria.

Question 41

During the assembly of the flagellar filament, the flagellin protein monomers assemble at the cell proximal base of the flagellum.

Question 42

Archaeal flagella are superficially similar to bacterial flagella, although archaeal flagella are much thicker than bacterial flagella.

Question 43

Small circular DNA molecules capable of replicating and containing genes that are useful but not necessary to the bacterium are called __________.

Question 44

Bacteria have a region of the cytoplasm known as the __________, which is not bounded by a membrane but contains the chromosome.

Question 45

_______ are the site of protein synthesis in the cell.

Question 46

Which of the following is not true of bacterial plasmids?

A) They can replicate independently of the chromosome.
B) They may carry genes for drug resistance.
C) They are required for host growth and/or reproduction.
D) They may carry genes that enhance survival of the bacterium under certain conditions.

Question 47

Chemotaxis is a process by which bacteria

A) move toward an attractant or away from a repellent.
B) avoid phagocytosis.
C) respond metabolically to the presence of autoinducer molecules.
D) move on solid surfaces by means of type IV fimbriae.

Question 48

The hydrocarbons found in the membranes of archaea are identical to those found in bacteria.

Question 49

Export of flagellin subunits is mediated by

A) an apparatus in the basal body of the flagellum that is related to the type II secretion pathway.
B) the type I secretion pathway.
C) an apparatus in the basal body of the flagellum that is related to the type III secretion pathway.
D) none of the above.

Question 50

Sedimentation coefficients are proportional to the molecular weight of a particle and are not affected by the volume and shape of the particle.

Question 51

The power used by most flagellar motors is produced by

A) synthesis of glucose
B) ATP hydrolysis
C) proton motive force (PMF)
D) all of the above

Question 52

Matching: Match the definition with the word.
1) monotrichous
2) peritrichous
3) lophotrichous
4) amphitrichous
a. a single flagellum
b. a single flagellum at each pole of an organism
c. a cluster of flagella at one or both ends of an organism
d. a relatively even distribution of flagella over the entire surface of the bacterium

Question 53

Intracellular granules of organic or inorganic material that are stockpiled by bacteria for future use are called __________.

Question 54

Some species of aquatic bacteria use inclusion bodies known as ________ to orient themselves in Earth's magnetic field.

Question 55

The type III bacterial protein secretion machinery:

A) has a needlelike structure through which proteins are secreted.
B) includes structural features that may be evolutionarily related to the basal bodies of bacterial flagella.
C) is found in gram-negative bacteria.
D) all of the choices are correct

Question 56

The rotation of bacterial flagella is powered by ATP hydrolysis.

Question 57

Bacterial flagella are composed of three parts: the ______ body, which is embedded in the cell, the hook, and the _______, which is the longest part of the flagellum.

Question 58

Proteinacious projections from the surface of a bacterium that are used to mediate conjugation are called sex __________, whereas projections that mediate attachment to surfaces such as host cells are called __________.

Question 59

Bacterial and archaeal ribosomes are known as _____ ribosomes, based on their sedimentation coefficient.

A) 50S
B) 30S
C) 80S
D) 70S

Question 60

Some photosynthetic bacteria produce gas vacuoles that regulate their buoyancy but contain no lipid.

Question 61

__________ is the main part of the process through which a vegetative cell is formed from an endospore.

Question 62

In many spirochetes, multiple flagella combine to form a bundle known as a(n) ____________ fibril, which winds around the cell and confers motility on the cell.

Question 63

__________ is the process through which endospores are formed within a vegetative cell.

Question 64

Endospores represent a challenge to the fields of industrial and medical microbiology because

A) they are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive.
B) endospore-forming organisms are often dangerous pathogens.
C) endospores are significantly smaller than vegetative cells.
D) endospores are resistant to harsh environments, thus allowing survival of endospore-forming organisms under conditions in which non-endospore-forming cells would not survive, and endospore-forming organisms are often dangerous pathogens

Question 65

Twitching or gliding motility involves

A) type IV pili.
B) axial fibrils.
C) movement of slime.
D) both type IV pili and movement of slime can be involved in twitching or gliding motility.

Question 66

The bacterium
E. coli swims in a straight line, called a __________, for a few seconds; then it stops, __________, then swims away in a new direction.