Microbiology Test 1 chapter 3

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The prokaryotic ribosome is a ________S ribosome

70

The density of the ribosome in a prokaryote is:

70S

Which staining technique allows differentiation of mycobacterial cells?

Acid fast stain

Which of the following are functions of the glycocalyx?

Adherence and protection

Members of the Domain ______ have peptidoglycan in their cell walls, whereas members of the Domain ________ have unique cell wall composition.

Bacteria ; Archaea

Put the following in order with the group containing the most organisms at the top. Strain Species

Species Strain

______ possess wound DNA enclosed in a nucleus and membrane bound organelles whereas _______ cells do not encase their DNA or organelles in a membrane

Eukaryotes ; prokaryotic

True or False: The gram negative cell wall has more peptidoglycan than the gram positive cell wall

False

True or False: The gram-negative cell wall has more peptidoglycan than the gram-positive cell wall.

False

The ____ stain techniques allows a microbiologist to differentiate bacteria based on their cell wall composition/structure

Gram

The discoverer of a staining technique for the differentiation of bacteria based on their cell walls was named Hans Christian ______

Gram

Which type of cell walls are thicker?

Gram positive

______ are able to flourish at high temperatures such as those found in thermal heat vents and volcanic waters

Hyperthermophiles

Bacteria that lose their cell wall during some point in their life cycle are known as __________ __________.

L - forms

When a bacterial cell loses its cell wall it is known as a(n):

L form

When a bacterial cell loses its cell wall, it is known as a(n):

L form

Which of the following are types of flagellar arrangements with more than one flagellum?

Peritrichous, Amphitrichous, Lophotrichous

Which of the following describes cocci in irregular clusters?

Staphylococci

Gram negative bacteria are the only type of bacteria that have been found to possess which external appendage?

Pilus

The hollow tubular appendage on a capsule is a?

Pilus

What term distinguishes between different bacteria based on the immunological response they elicit in a host?

Serotype

The following describes cocci in chains?

Streptococci

What is the difference between a true nucleus and a nucleoid?

a true nucleus is surrounded by a membrane whereas a nucleoid is not

The ______ - _______ stain technique would be used to discover Mycobacterium tuberculosis in a sputum sample.

acid - fast

The two main functions of the glycocalyx are _____ and ______

adherence, protection

A cell membrane, ribosomes, chromosome(s) and cytoplasm are found in _______ bacterial cells.

all

Which is true regarding all prokaryotes?

all lack a nucleus

The glycocalyx is important in the ability of bacteria to cause infection because it can?

allows for the formation of biofilms, helps the bacteria evade immune defenses, allows the bacteria to adhere well to medical devices

What does selectively permeable mean?

allows the passage of some materials but not all materials move through freely

What is the glycocalyx?

an extracellular coating that provides protection to the cell

Plasmids typically carry _____ genes

antibiotic resistance ; nonessential

Prokaryotic cells that are related to eukaryotes but similar in structure to bacteria are called _______

archaea

The main function of fimbriae is _______ to cells and other surfaces

attachment

A(n) ________ filament is a periplasmic flagellum found in some spirochete bacteria.

axial

Twisting or flexing of spirochete bacteria is attributed to its:

axial filaments

Peptidoglycans are components of the cell walls in ________.

bacteria

Why is it difficult to group bacteria into species?

bacteria can alter their genetic makeup, bacteria do not use a typical mode of sexual reproduction, bacterial cells can accept genetic material from other sometimes unrelated cells

The _____ is the name given to a structure external to and bound tightly to the cell wall that is made of polysaccharides and proteins and contributes to the pathogenicity of the organism

capsule

Which of the following structures is external and can protect the bacterial cell from various host immune responses?

capsule

Which of the following acts as a selective barrier between the internal and external contents of the cell?

cell membrane

Penicillin is ineffective against Mycoplasma because the organism lacks a ________ ___________ which is the primary target of penicillin.

cell wall

The ______ ______ is the structure used by the Bergey's Manual of Determinative Bacteriology to classify bacteria into taxonomic divisions such as Gracilicutes and Firmicutes.

cell wall

What structure is used in the Bergey's Manual of Determinative Bacteriology to divide prokaryotes into four major divisions?

cell wall

The prefix "strepto" is used to indicate that the cells are arranged in ?

chains

To move towards a chemical attractant by flagellar motion is referred to as positive

chemotaxis

The hereditary material of a bacterial cell is a (normally) single circular strand of DNA known as the bacterial _______, which is aggregated in the nucleoid

chromosome

The genetic exchange of material through pili is termed _____

conjugation

The genetic exchange of material through pili is termed __________

conjugation

The correct order of the four reagents of gram stain?

crystal violet, gram's iodine, alcohol, safranin

The internal gelatinous matrix of a cell, mostly composed of water, is referred to as _________.

cytoplasm

The ______ is a network of actin and tubulin filaments tat are located just under the cell membrane and that contribute to cell shape

cytoskeleton

What internal structure contributes to cell shape and division?

cytoskeleton

In bacteria, sporulation is the process of ______ formation

endospore

Depletion of nutrients like carbon and nitrogen can result in the formation of ________ in some bacteria.

endospores

Diseases such as anthrax, tetanus, gas gangrene and botulism are caused by bacteria that are able to form?

endospores

______ are for cell survival under extreme environmental conditions, rather than reproduction.

endospores

The lipid portion of lipopolysaccharide (LPS) is also known as _____

endotoxin

What roles do teichoic and lipoteichoic acid play in gram-positive cells?

enlargement during cell division, maintenance of the cell wall, contribute to charge of the cell surface

What general word is used to describe a preference for an environment such as high heat or high levels of salt?

extremophile

Organisms such as the Archaea, are termed ________ because they are capable of living in very harsh environments

extremophiles

True or False: All prokaryotes have a cell wall

false

True or False: Penicillin is an effective antibiotic against Mycoplasma.

false

True or False: The cell wall of gram-negative bacteria is thicker than the cell wall of gram-positive bacteria

false

The lipid portion of lipopolysaccharide is known as endotoxin because it can cause:

fever and shock

Which appendage provides the ability to attach to surfaces and other cells?

fimbriae

_______ are used for attachment

fimbriae

The basal body, hook, and filament are components of _______ in prokaryotes.

flagella

The ______ is a polysaccharide protective coating outside of the bacterial cell wall that is called either a capsule or slime layer based on its structure

glycocalyx

The outer coating of many bacterial cells is called the?

glycocalyx

The ______ stain technique allows a microbiologist to differentiate bacteria based on their cell wall composition/structure

gram

What staining technique is most commonly used to differentiate most bacteria based on their cell wall structure?

gram stain

Lipopolysaccharide is a component of cell membrane of which cell type?

gram-negative cells

To determine whether bacterial cells are motile, one can observe them microscopically in a ________ drop slide.

hanging

Because endospores are resistant to ________, food must be canned using pressurized steam to ensure sterility

heat

Which group of bacteria grows at very high temperatures?

hyperthermophiles

Cytoplasmic _____ such as granules or vesicles, can store organic and inorganic nutrients and even gases or magnetic iron oxides

inclusions

Organic and inorganic nutrients can be stored in bacterial cells as:

inclusions

Organic and inorganic nutrients can be stored in bacterial cells as?

inclusions

What is the purpose of mycolic acid in the mycobactyerial cell wall?

it reinforces the cell wall and makes the bacterium resistant to certain chemicals and dyes

LPS is the abbreviation for _______

lipopolysaccharide

A tuft of flagella from a single site is referred to as a _______ arrangement, whereas flagella dispersed over the surface of the cell is referred to as _____

lophotrichous ; peritrichous

Cell breaking or rupturing is known as cell ______

lysis

_______ is what occurs when a cell breaks or ruptures

lysis

What roles do teichoic and lipteichoic acid play in gram positive cells?

maintenance of the cell wall; enlargement during cell division; contribute to charge of the cell surface

All bacteria possess a cell _______ but not all bacteria possess a cell _________

membrane ; wall

Organisms that are able to convert carbon dioxide and hydrogen into methane are known as __________

methanogens

Which type of organism converts CO2 and H2 into CH4 (methane)

methanogens

A cell wall and some form of glycocalyx are found in _______ bacterial cells.

most

The ability to move is referred to as __________

motility, self propulsion

The mycobacterial cell wall is reinforced with ______ acid

mycolic

The _____ bacteria have no cell wall but have a cytoplasmic membrane that is stabilized by sterols:

mycoplasma

The ______ bacteria naturally have no cell wall, but have a cytoplasmic membrane that is stabilized by sterols.

mycoplasma

The _______ bacteria have no cell wall, but have a cytoplasmic membrane that is stabilized by sterols.

mycoplasma

Bacteria that are in close proximity may communicate via structures known as _______

nanowires

Only gram-______ bacteria possess an outer membrane

negative

Only gram-_______ bacteria possess an outer membrane.

negative

To date, true pili have only been found on gram- ______ bacteria

negative

To date, true pili have only been found on gram- _______ bacteria

negative

Gram-______ cell walls are thinner than Gram-______ cell walls, providing them with relatively greater flexibility and sensitivity to lysis.

negative ; positive

Depletion of ___________ is the stimulus for the formation of endospores

nutrients

The phospholipid barrier surrounding the peptidoglycan layer in gram-negative bacteria is called the _______ membrane

outer

The phospholipid barrier surrounding the peptidoglycan layer in gram-negative bacteria is called the _______ membrane.

outer

The prefix "diplo" is used to indicate that cells are arranged in:

pairs

A major structural component of the lipid bilayer in a cell membrane are _________, which comprise 30-40% of the membrane mass

phospholipids

During ________, bacterial cells move by flagellar motion in response to light

phototaxis

Small proteinaceous appendages in gram-negative bacteria that function in DNA exchange are called conjugation ____

pili

A ______ is a hollow, protein tube that facilitates the transfer of genetic material between bacterial cells

pilus

An appendage which forms a channel for the exchange of genetic material during bacterial conjugation is called a ___________

pilus

A ______ is an extrachromosomal piece of DNA that contains genes not essential for cell growth.

plasmid

Which phrase means that a cell can have various shapes?

pleomorphic

Teichoic acid and lipoteichoic acid are:

polysaccharides embedded in the cell wall of gram-positive bacteria

________ are specialized proteins located in the outer membrane of gram-negative cells.

porins

Archaea are:

prokaryotic, more closely related to the Eukarya than the bacteria, often able to exist in extreme environments

What are porins?

protein channels that span the outer membrane

What two macromolecules make up the major components of cell membranes?

proteins ; lipids

A gram positive cell that has lost its cell wall and is now very susceptible to lysis is referred to as a:

protoplast

A gram-positive cell that has lost its cell wall becomes an L-form known as a.

protoplast

What is the primary function of the capsule?

provides protection

Refrigerators are excellent environments to encourage the growth of ________

psychrophiles

Which group of bacteria grows at very low temperatures

psychrophiles

Proteins are synthesized on the _______, a small spherical structure located int he cytoplasm or attached to the rough endoplasmic reticulum (RER)

ribosome

The site of protein synthesis in a cell, known as the ________ , is composed of rRNA and protein.

ribosome

Which organelle is responsible for synthesizing protein?

ribosome

Which organelle's small and large subunits are composed of rRNA and protein?

ribosome

Which structures are possessed by ALL bacteria?

ribosomes, cell membrane, chromosomes

Counterclockwise rotation of the flagellum causes a bacterial cell to swim or ______ towards a stimulus, interrupted by clockwise rotation in which the cell _____ and changes its course

run ; tumble

The cell membrane is a _____ permeable barrier of the cell

semi

One way to detect motility in the laboratory is to stab cells into what kind of medium?

semisolid

______ refers to a specific member of a species based on the host's antibody response.

serotype

______ refers to a specific member of a species based on the hosts antibody response

serotype

Choose the characteristic that is true for archaea but not bacteria

similar ribosome structure to eukaryotes

Some bacteria are covered with a loose shield called a ________ _______ that protects the cell from dehydration and loss of nutrients

slime layer

a type of glycocalyx called the _____ is loosely attached to the bacterial cell and protects it from dehydration and loss of nutrients.

slime layer

The two types of glycocalyx in bacteria are:

slime layer ; capsules

A "strain" is a subgroup of a _____.

species

A "strain" is a subgroup of a ________.

species

A "type" is a subgroup of a bacterial _______

species

A gram negative cell that has lost its cell wall but retained part of its outer membrane is referred to as a:

spheroplast

The L-form that arises when gram-negative bacteria lose their cell wall but retain part of their outer membrane is called a.

spheroplast

______ is the process of endospore formation

sporulation

The prefix "______" means "in a chain"

strepto -

What is the primary function of endospores?

survival

Which structure accounts for the different results of the Gram stain

the cell wall

True or False: A nucleus is surrounded by a membrane but a nucleoid is not

true

True or False: Bacterial endospores are more resistant to disinfectants than vegetative cells.

true

True or False: Endospores are resistant to ordinary boiling

true

True or False: Mycoplasmas are pleomorphic

true

Which is more impervious to the action of antimicrobial chemicals?

typical gram negative bacteria

A curved bacterial cell is a:

vibrio

The gram stain differentiates bacteria based upon structural differences of the bacterial cell ________

wall

The cell envelope is composed of cell _______ and the cell _______

wall ; membrane

The following are required for endospores to germinate.

water, a specific chemical or environmental stimulus

Domain Archaea is most closely related to Domain _________ because they share rRNA sequences and similar ribosomal structure/function

Eukarya

Which of the following diseases are caused by endospore forming bacteria?

Botulism, Anthrax, Tetanus

Which structures are possessed by the majority of but not all bacteria?

Cell wall, glycocalyx

Bergey's Manual of ______ Bacteriology is used by microbiologists whose primary interest is identification of prokaryotes, while Bergey's Manual of _________ Bacteriology is used by those who are also interested in the evolutionary relationships of prokaryotes.

Determinative ; Systematic

True or False: Endospores are resistant to ordinary boiling

True


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