Deck 3: Cell Structure and Function in Bacteria and Archaea

Question 1

What is the biological function of endospores?

A) They are bacterial reproductive structures.
B) They are formed as evaginations of the bacterial cell walls.
C) They enable organisms to endure extremes of temperature, drying, and nutrient depletion.
D) All of the above are endospore functions.

Answer 1

C

Question 2

Nutrients and waste products pass into and out of a cell in proportion to the cell's size.

A) direct
B) logarithmic
C) inverse
D) exponential

Answer 2

C

Question 3

The cytoplasmic membrane could best be described as

A) a passive conduit for intracellular transport.
B) an impermeable barrier.
C) a highly selective permeability barrier.
D) slightly permeable to water but impermeable to metabolic solutes.

Answer 3

C

Question 4

One of the many types of proteins found in the cytoplasmic membrane is involved in the chemotactic response and is called a

A) porin.
B) binding protein.
C) hydrolytic enzyme.
D) chemoreceptor.

Question 5

Translocases are specific for the transport of

A) nucleic acids.
B) carbohydrates.
C) proteins.
D) lipids.

Question 6

In gram- positive Bacteria, the cell wall may be up to peptidoglycan.

A) 72%
B) 25%
C) 90%
D) 48%

Question 7

Carrier- mediated transport is necessary when

A) the level of nutrients in nature is very low.
B) diffusion will not allow adequate amounts of a substance to enter the cell.
C) movement into the cell is against a concentration gradient.
D) All of the above are true.

Question 8

The terms "run" and "tumble" are generally associated with

A) cell membrane structures.
B) clustering properties of certain rod- shaped bacteria.
C) movement of the cell.
D) cell wall fluidity.

Question 9

The tetraether molecule within the membrane structure of the yields a lipid .

A) Archaea / bilayer
B) Bacteria / monolayer
C) Archaea / monolayer
D) Bacteria / bilayer

Question 10

Which is a function of the cytoplasmic membrane in prokaryotes?

A) It is an anchor for many proteins involved in bioenergetic reactions and transport.
B) It functions as a permeability barrier.
C) It is a major site of energy conservation.
D) All of these are functions of the cytoplasmic membrane.

Question 11

The polysaccharide pseudomurein is present in the walls of

A) some Archaea.
B) Bacteria and Archaea.
C) Eukarya.
D) Bacteria.

Question 12

Negatively charged molecules that are partially responsible for the negative charge of the gram- positive bacterial cell surface are

A) teichoic acids.
B) peptide interbridges.
C) phospholipids.
D) diaminopimelic acids.

Question 13

Which of these statements is TRUE?

A) The gram- positive wall contains a thick peptidoglycan layer and is more complex than the gram- negative wall.
B) The gram- positive wall contains a thick peptidoglycan layer but is about as complex as the gram- negative wall.
C) The gram- negative wall contains a thick peptidoglycan layer and is more complex than the gram- positive wall.
D) The gram- positive wall contains a thick peptidoglycan layer but is less complex than the gram- negative wall.

Question 14

An endotoxin is

A) a toxin known for its primary attack on the epidermis of mammals.
B) the toxin produced in the periplasm of most bacteria.
C) the toxic portion of the LPS.
D) a toxin produced within archaeal cells.

Question 15

Hydrolytic enzymes function in the

A) chemotactic response, particularly in gram- negative Bacteria.
B) regeneration of the periplasm.
C) transport of substrates within the cell.
D) initial degradation of nutrients.

Question 16

The prokaryotic transport system that involves a substrate- binding protein, a membrane- integrated transporter, and an ATP- hydrolyzing protein is

A) group translocation.
B) the ABC system.
C) symport.
D) simple transport.

Question 17

Regarding membrane linkages, which statement is TRUE?

A) Archaea have ester linkages; Eukarya have ether linkages.
B) Bacteria and Eukarya have ester linkages; Archaea linkages are not yet known.
C) Bacteria and Eukarya have ester linkages; Archaea have ether linkages.
D) Eukarya have ester linkages; Bacteria have ether linkages.

Question 18

When does endospore formation commence?

A) following bacterial death
B) when bacterial growth ceases due to limitation of an essential nutrient
C) when bacteria are dividing exponentially
D) when the bacterium is undergoing binary fission

Question 19

Bacteria with appendages

A) have filaments that are commonly called appendages.
B) have the basic characteristics of eukaryotic cells.
C) possess tubular or stalk- like extensions of their cells.
D) do not exist.

Question 20

Which statement is TRUE?

A) The phosphotransferase system has nothing to do with group translocation.
B) The phosphotransferase system is synonymous with group translocation.
C) The phosphotransferase system is a type of group translocation.
D) Group translocation is a part of the phosphotransferase system.

Question 21

Which of the following statements is/are TRUE?

A) Fimbriae enable cells to stick to surfaces.
B) Pili serve as receptors and facilitate genetic exchange between prokaryotic cells.
C) Fimbriae are generally shorter and more numerous than flagella.
D) All of the above are true.

Question 22

Aquaporins are

A) molecules that prevent water from crossing a membrane.
B) cations bound to water molecules.
C) water transport proteins.
D) enzymes involved in the generation of water within cells.

Question 23

Sterols are virtually always

A) absent in eukaryotic membranes but present in prokaryotic membranes.
B) present in eukaryotic membranes but absent in prokaryotic membranes.
C) absent in both eukaryotic and prokaryotic membranes.
D) present in both eukaryotic and prokaryotic membranes.

Question 24

The term given to the phospholipid bilayer and the proteins embedded within it is
.

Question 25

Glycogen granules

A) cannot be detected by light microscopy, even if iodine is added.
B) function as storage depots for carbon and energy.
C) are derived directly from either PHB or PHA.
D) None of the above applies to glycogen granules.

Question 26

Although the inner leaflet of the gram- negative outer membrane contains phospholipids, the outer leaflet of the outer membrane contains

A) lipopolysaccharide (LPS).
B) pseudopeptidoglycan.
C) poly- fi- hydroxybutyric acid (PHB).
D) lipoteichoic acids.

Question 27

Which statement is TRUE?

A) Lophotrichous flagella are tufts on the "ends" of bacterial cells; peritrichous flagella are individual flagella on the "ends" of bacterial cells.
B) Polar flagella are individual flagella on the "ends" of bacterial cells; peritrichous flagella are tufts on the "ends" of bacterial cells.
C) Peritrichous flagella are all over the bacterial cells; lophotrichous flagella are tufts on the "ends" of bacterial cells.
D) Polar flagella are all over the bacterial cells; lophotrichous flagella are individual flagella on the "ends" of bacterial cells.

Question 28

The proton motive force is responsible for driving many energy- requiring functions in the cell, including some forms of , , and biosynthesis of _ .

Question 29

The membrane of a gas vesicle is composed of

A) protein.
B) various phospholipids.
C) carbohydrate.
D) both glycoproteins and phospholipids.

Question 30

Twitching motility is an unusual form of motility in some bacteria that is a result of a class of surface structures known as .

Question 31

An organism of the genus Staphylococcus is , while an organism of the genus Spirochaeta is .

A) spherical / coiled
B) spherical / rod shaped
C) coiled / spherical
D) rod shaped / coiled

Question 32

Morphology is a term that refers to the of an organism.

A) appendages
B) attachment sites
C) size
D) shape

Question 33

Which of the following statements is FALSE?

A) Flagella rotate at a constant speed.
B) A flagellar protein subunit is flagellin.
C) In flagellar motion, the basal body acts as a motor.
D) The hook is the wider region at the base of the flagellum.

Question 34

A major function of prokaryotic gas vesicles is

A) to keep the cell's organelles separated during flagellar motion.
B) to serve as a reservoir for oxygen and carbon dioxide.
C) to confer buoyancy on cells by decreasing their density.
D) none of the above.

Question 35

Bacteria stain as gram- positive or gram- negative because of differences in the cell

A) wall.
B) nucleus.
C) chromosome.
D) cytoplasm.

Question 36

The lipopolysaccharide (LPS) layer is found ONLY in the cell wall of

A) gram- negative Bacteria.
B) Eukarya.
C) gram- positive Bacteria.
D) Archaea.

Question 37

A general term to describe intracellular accumulations of polyphosphate, elemental sulfur, or magnetosomes is a(n) .

Question 38

Some of the intestinal symptoms elicited by pathogens such as Salmonella, Shigella, and
Escherichia are due to the presence of .

Question 39

The periplasm is a(n)

A) part of the outer cell membrane of gram- negative organisms.
B) alternate name for the inner cell membrane of any prokaryotic cell.
C) region between the cytoplasmic membrane and the outer membrane of gram- negative Bacteria.
D) part of the inner cell membrane of gram- negative organisms.

Question 40

The energy source derived from the charge separation across the cytoplasmic membrane is referred to as the .

Question 41

Small acid- soluble proteins (SASPs) are found in high numbers within the core of
, which help to protect DNA from . They also serve as a(n) source during outgrowth.

Question 42

A phototrophic bacterium swims outside the illuminated field of view of the microscope, reverses direction, and scurries back into the lighted area. This is an example of .

Question 43

The lipid portion of the lipopolysaccharide (LPS) is known as lipid A.

Question 44

An individual rod- shaped bacterium is also called a(n) morphology, while two or more of these are collectively described as _ _. Similarly, one is a spherical bacterium, and two or more are termed .

Question 45

As a general statement, inclusions function as energy reserves or as a reservoir of structural building blocks.

Question 46

A purple bacterial cell is interpreted as gram- positive when it forms insoluble crystal violet- iodine complexes within the cell during the Gram stain.

Question 47

Lysozyme is an enzyme that can ultimately lyse and kill bacterial cells by breaking
fi- 1,4- glycosidic bonds in peptidoglycan.

Question 48

In general, swimming is performed with flagella, whereas gliding uses other cellular components such as pili.

Question 49

Porins are channels in the outer membranes of gram- positive Bacteria.

Question 50

In general, lipids in the archaeal membrane lack true fatty acids.

Question 51

The proton motive force helps drive cellular functions that require energy by maintaining a positively charged side of the cell and the other negatively charged.

Question 52

Eukaryotes have in their cytoplasmic membranes, which serve to strengthen and stabilize the membrane and make it less flexible. Many Bacteria have similar molecules, known as _ , in their membranes that likely have a similar role.

Question 53

Some membrane proteins are involved in bioenergetic reactions, while others are involved in membrane transport.

Question 54

Smaller prokaryotic cells generally grow faster than larger ones due to a higher surface- area- to- volume ratio.

Question 55

Hopanoids strengthen the plasma membrane in prokaryotes and form a highly rigid membrane, analogous to the function of cholesterol in animals.

Question 56

The rigid layer that is present in the cell walls of Bacteria that is primarily responsible for the strength of the wall is known as .

Question 57

Pathogenic bacteria that contain S- layers are protected against host defense mechanisms.

Question 58

Despite the invariance of the peptidoglycan backbone's structure, there are more than 100 different types of peptidoglycan.

Question 59

Teichoic acids are commonly found in gram- negative cell walls.

Question 60

The peptide interbridge crosslinking is found ONLY in the cell walls of Bacteria.

Question 61

In phototaxis, photosynthetic organisms move away from a light source.

Question 62

Elaborate on why the discovery of endospores was important to microbiology.

Question 63

Describe the processes of endospore formation and germination.

Question 64

What is the evolutionary advantage of the monolayer often found in archaeal membranes?

Question 65

Chemotaxis is a sensory response affecting flagellar function.

Question 66

Describe the growth of a flagellum.

Question 67

Explain what would happen to a motile bacterium undergoing chemotaxis if the Fli proteins suddenly ceased to function.

Question 68

Organisms may respond to temporal rather than spatial gradients.

Question 69

Explain the differences between uniporters, symporters, and antiporters.

Question 70

Compare and contrast fimbriae and pili.

Question 71

Compare and contrast a capsule and a slime layer in terms of composition, organization, and function.

Question 72

Photoreceptors are analogous to chemoreceptors in that they are both proteinaceous sensors.

Question 73

Explain why prokaryotes tend to adapt more rapidly to changing environmental conditions and more easily exploit new habitats than do eukaryotes.

Question 74

Compare and contrast the location and activities of periplasm- binding proteins of ABC transport systems in gram- negative and gram- positive Bacteria.

Question 75

Compare and contrast aerotaxis and osmotaxis.

Question 76

Both hydrophilic and charged molecules readily diffuse through the cytoplasmic membrane.

Question 77

Speculate on why all prokaryotic transport systems require energy in some form or another.

Question 78

The existence of nanobacteria was confirmed in 2006.

Question 79

Poly- fi- hydroxybutyric acid (PHB) is a carbon- and energy- storing polymer.

Question 80

ABC transport systems are present in both gram- positive and gram- negative Bacteria.