microbio final mcgraw hill questions

Plants are dependent on microorganisms for

A) providing complex proteins

B) providing simple carbohydrates

C) providing oxygen in a usable form

D) changing atmospheric nitrogen to a usable form

E) providing water

D

Identify which of the following is/are eukaryotes:

1. Algae

2. Bacteria

3. Viruses

4. Prions

5. Protozoa

1, 5

T/F: Viruses and bacteria are both based on the unit of a cell.

false

Which of the following statements about bacteria is FALSE?

A) most bacteria are actually helpful, not harmful.

B) most bacteria have been grown in culture and characterized.

C) prokaryotic cells have a nucleoid containing DNA.

D) yogurt contains many bacterial cells.

E)bacterial cell walls contain peptidoglycan.

B

Which pair has members that are most similar in appearance?

A) algae and archaea

B) bacteria and viruses

C) viruses and algae

D) archaea and bacteria

E) fungi and algae

D

Microbes are useful research tools because

A) they are cheap and easy to grow in the laboratory

B) they can be grown in large number very easily

C) All of theses answer choices are correct

D) they use the same metabolic pathways as eukaryotic cells

E) they are cheap and easy to grow in the laboratory AND they are the same metabolic pathways as eukaryotic cells

C

Microorganisms are involved in

A) causing disease

B) curing/treating disease

C) preparing food

D) cleaning up pollutants

E) All of these answer choices are correct

E

You are examining a pea plant that is showing signs of disease—brown leaves and no pea pods. You isolate an agent from the plant that only contains RNA and protein. This is a(n)

A) virus

B) viroid

C) bacterium

D) protozoan

E) fungus

A

Which of the following is found only in bacteria?

A) ATP

B) phospholipids

C) chlorophyll

D) peptidoglycan

E) DNA

D

If you discovered a new protozoan, to which domain(s) would it belong?

A) prokarya or bacteria

B) prokarya

C) prokarya or achaea

D) bacteria and archaea

E) eukarya

E

The terminal electron acceptor in respiration may be

A) NAD, oxygen, OR nitrate.

B) an inorganic molecule, water, OR oxygen.

C) oxygen nitrate, OR an inorganic molecule.

D) NAD, nitrate, OR an inorganic molecule.

E) NAD, water, OR an inorganic molecule.

C

Fermentation

A) uses an organic molecule as the final electron acceptor AND is necessary in some organisms to produce reduced electron carriers.

B) results in the production of a large amount of ATP.

C) uses an organic molecule as the final electron acceptor.

D) uses an inorganic molecule as the final electron acceptor.

E) is necessary in some organisms to produce reduced electron carriers.

C

Proton motive force

A) is used to synthesize ATP

B) is used to produce NADH

C) is used to synthesize ADP

D) is used to produce FADH2

E) uses ADP and ATP

A

The most common starting pathway for the breakdown of sugars

A) anabolism

B) fermentation

C) glycolysis

D) oxidation

E) respiration

C

What happens to the carbon molecules in the pyruvic acid that goes through the TCA cycle?

A) they form "energy storing molecules" for the cell

B) they are excreted as waster organic acids

C) they get incorporated into cell material

D) they become phosphorylated

E) they become carbon dioxide

E

Which of the statements about catabolism and anabolism is TRUE?

A) They refer only to the reactions dealing involved in the metabolism of lipids.

B) The intermediates of catabolism serve as products in anabolism.

C) The energy gathered during catabolism is used during anabolism.

D) They refer only to the reactions involved in carbohydrate synthesis.

E) The energy gathered during anabolism is used during catabolism.

C

Enzymes speed up reactions by

A) raising activation energy

B) electron carriers

C) reducing entropy

D) producing heat

E) lowering activation energy

E

Enzymes act on _____ to generate ____.

A) glucose, anabolites

B) substrates, prroducts

C) products, substrates

D) products, catabolites

E) ATP, glucose

B

Biosynthetic reactions that require energy for the conversion of molecular subunits into larger molecules are called

A) anabolic reaction

B) precursor molecules

C) canabolic reactions

D) kinetic energy

E) catabolic reactions

A

Bacteria that can absorb light energy and convert it into ATP are commonly called

A) metatrophs

B) chemotrophs

C) phototrophs

D) cytochromes AND chemotrophs

E) cytotrophs

C

Pyruvate can be metabolized along two major routes. They are

A) oxidation and reduction

B) fermentation and oxidation

C) anabolism and catabolism

D) fermentation and respiration

E) metabolism and anabolism

D

NAD in its reduced form is symbolized as

A) NAD

B) NADP

C) NADP+

D) NADH

E) NAD-

D

The name given to the reaction involving removal of electrons or hydrogen atoms from a compound is

A) metabolism

B) glycolysis

C) oxidation

D) reduction

E) respiration

C

The name given to the reaction involving addition of electrons or hydrogen atoms to a compound is

A) metabolism

B) respiration

C) oxidation

D) glycolysis

E) reduction

E

Enzymes act as

A) reducters

B) catalysts

C) products

D) catabolites

E) substrates

B

Experiments designed by ______ suggested that living cells caused the fermentation of sugar to produce alcohol.

A) Wohler

B) Pasteur

C) Fleming

D) Jenner

E) Koch

B

Allosteric enzymes

A) have an additional binding site that is involved in regulating enzyme activity.

B) are twice as fast as single-site enzymes.

C) have an additional binding site that is never involved in regulating enzyme activity.

D) are used to bind to other enzymes.

E) may bind two substrates at the same time.

A

Environmental factors that may affect enzyme activity include

A) temperature, pH, AND salt

B) pH

C) salt

D) temperature

E) none of the answer choices is correct

A

Which of the following processes generates the greatest amount of energy?

A) phosphorylation

B) glycolysis

C) aerobic respiration

D) fermentation

E) krebs cycle

C

A phage that replicates inside the host cell and then lyses its host during its release is a

A) latent phage

B) lysogenic phage

C) temperate phage

D) dormant phage

E) virulent or lytic phage

E

Which of the following is NOT true about an ideal vector?

A) A vector contains an origin of replication.

B) A vector contains an RNA primer.

C) A vector has a restriction enzyme recognition site.

D) A vector may be a plasmid or bacteriophage.

E) A vector contains a selectable marker.

B

When a vector that uses the lacZ gene as a second marker is used in a cloning experiment, bacteria that contain the recombinant DNA will give rise to

A) red colonies

B) white colonies

C) blue colonies

D) cream colonies

E) all of the answer choices are correct

B

The molecule(s) that act as molecular glue to bind DNA fragments together is/are

A) DNAse

B) DNA ligase

C) ligandase

D) polymerase

E) DNAse AND ligandase

B

Short tandem repeats (STRs)

A) are important sites in vectors where foreign DNA can be integrated.

B) are DNA fragments generated during PCR.

C) are errors that can arise during DNA sequencing.

D) are useful in identifying specific individuals.

E) are generally found in exons.

D

The polymerase chain reaction is used to

A) amplify mRNA

B) produce long polymers of carbohydrates to be used in electrophoresis.

C) produce proteins

D) amplify certain sections of DNA

E) produce long polymers of amino acids to be used in electrophoresis.

D

The molecules used to cut target DNA in genetic engineering are

A) DNA ligases

B) RNA polymerases

C) proteases

D) restriction enzymes

E) exonucleases

D

The correct order for the stages of a phage infection is

A) attachment, replication of nucleic acid and protein, penetration, transcription, assembly, release.

B) attachment, replication of nucleic acid and protein, assembly, penetration, transcription, release.

C) penetration, transcription, attachment, replication of nucleic acid and protein, assembly, release.

D) transcription, attachment, replication of nucleic acid and protein, assembly, penetration, release.

E) attachment, penetration, transcription, replication of nucleic acid and protein, assembly, release.

E

Dideoxynucleotides

A) act as chain initiators AND have two additional hydroxyl groups at the 2' and 3' carbons.

B) are useful in nucleic acid sequencing AND have two additional hydroxyl groups at the 2' and 3' carbons.

C) act as chain initiators AND are useful in nucleic acid sequencing.

D) are useful in generating proteins AND act as chain terminators.

E) are useful in nucleic acid sequencing AND act as chain terminators.

E

DNA molecules that contain pieces of DNA from two different sources are defined as

A) recombinant DNA

B) gene cloning

C) genetic engineering

D) mutation

E) biotechnology

A

Viruses that infect bacteria are referred to as

A) bacteriocidins

B) bacteriophages

C) viralcidens

D) bacterialogens

E) virophages

B

Common vectors used for cloning genes are

A) nucleotides

B) plasmids

C) bacteria

D) viruses AND plasmids

E) viruses

D

Taq polymerase is

A) an enzyme from Escherichia coli.

B) an RNA polymerase AND an enzyme from Escherichia coli.

C) an RNA polymerase.

D) a heat-stable DNA polymerase from Thermus aquaticus.

E) a reverse transcriptase.

D

The entire set of cloned fragments of the complete human genome is termed a

A) genetic set

B) DNA library

C) book genes

D) restructured genome

E) recombinant gene

B

The viral envelope closely resembles the

A) prokaryotic cell wall

B) eukaryotic cell wall

C) eurkaryotic cytoplasmic membrane

D) capsomere

E) cytoplasm

C

Identify the statement about digestion of DNA by restriction enzymes that is NOT true.

A) it produces sticky ends

B) it produces blunt ends

C) one strand of the DNA molecule is cut

D) it generates restruction fragments

E) both strands of the DNA molecule are cut

C

Outside of living cells, viruses are

A) using cillia to move to the next host

B) metabolically inert

C) gaining ATP from the mitochondria

D) scavenging glucose

E) replicating by binary fission

B

The protein projections on the surface of a virus that are involved in attachment to the host cell are called

A) spikes

B) pilli

C) suckers

D) hooks

E) cillia

A

Agarose gel electrophoresis separates nucleic acid fragments according to

A) density

B) type of 5C sugar

C) size

D) nucleobase sequence

E) shape

C

The shape of the virus is determined by its

A) spikes

B) nucleic acid

C) tail

D) capsid

E) envelope

D

The use of the suffix "ase" on a word denotes a(n)

A) enzyme

B) electron acceptor

C) substrate

D) substrate AND electron acceptor

E) product

A

Growth of a parasitic organism in or on the host is referred to as

A) colonization

B) infection

C) mutualism

D) commensalism

E) pathogenism

B

A disease-causing microorganism or virus is referred to as a(n)

A) avirulent infection

B) colony

C) commensal

D) pathogen

E) virulent

D

Bacteria that resist killing by complement proteins are termed

A) mutualistic AND serum resistant

B) balanced pathogens

C) serum resistant

D) mutualistic

E) serum strong

C

T/F: Infection always leads to disease.

false

Which of the following would NOT be considered virulence factor(s)?

A) adhesins

B) capsules

C) endotoxins

D) proteases

E) ribosomes

E

The infectious dose

A) is the same for all bacteria but varies for viruses.

B) is the same for all microorganisms.

C) is defined as the number of microbes needed to cause infection.

D) may be 10-100 cells for Salmonella.

E) is defined as the number of microbes needed to kill the host.

C

Opportunists or opportunistic pathogens

A) are never normal microbiota

B) always cause disease

C) are usually saprophyte, like fungi

D) are usually mutualistic

E) take advantage of special circumstances

E

Attributes of an organism that promote pathogenicity are called

A) pathogenic factors

B) mutualistic factors

C) virulence factors

D) colonization factors

E) disease factors

C

The series of steps used to connect an organism to a disease are known as

A) Lister's aseptics

B) Koch's postulates

C) Linnaeus' taxonomics

D) Bergey's manual

E) Pasteur's postulates

B

Which of the following members of the normal microbiota inhibit the growth of Candida albicans?

A) Staphylococci species

B) all of the answer choices are correct

C) Lactobacillus species

D) Propionibacterium species

E) E. Coli

C

Which of the following would be considered a sign of a disease?

A) throbbing pain

B) a rash

C) intense nausea

D) all of these are signs

E) severe headache

B

The lack of susceptibility to diseases of other species in humans may be due to the

A) presence of endotoxins.

B) lack of receptors that are recognized by adherence factors.

C) lack of any cytokine production.

D) presence of endotoxins AND secretion of exotoxins.

E) lack of any cytokine production AND secretion of exotoxins.

B

Organisms that are found together and interact on a more or less permanent basis are in a relationship termed

A) parasitism

B) transient microbiota

C) symbiosis

D) mutualism

E) variance

C

The series of steps used to connect an organism to a disease are known as

A) Lister's aseptics

B) Koch's postulates

C) Linnaues' taxonomics

D) Bergey's mannual

E) Pasteur's postulates

B

The symbiotic relationship wherein both partners benefit is termed

A) dysbiosis

B) independence

C) mutualism

D) parasitism

E) commensalism

C

A relationship in which one partner benefits and the other is harmed is termed

A) parasitism

B) commensalism

C) normal microbiota

D) independence

E) mutualism

A

The microorganisms that are regularly found in or on the body, yet do no apparent harm are called

A) transient microbiota

B) normal microbiota

C) abnormal microbiota

D) variant microbiota

E) random biota

B

A relationship in which one partner benefits and the other is unaffected is termed

A) mutualism

B) independence

C) commensalism

D) dysbiosis

E) parasitism

C

Adhesins are

A) exotoxins AND are involved in the first step of the infectious process.

B) involved in the first step of the infectious process AND are often found at the tip of pili.

C) often found at the tip of pili AND are endotoxins.

D) involved in the first step of the infectious process AND are endotoxins.

E) are exotoxins OR are endotoxins.

B

Virulent pathogens are

A) more likely to be opportunists

B) more likely to be pathogens

C) more likely to cause severe disease

D) unable to cause disease

E) most likely normal microbiota

C

The resolving power of a microscope is described as the ability of the microscope to

A) separate clearly two objects that are very close together

B) magnify an object

C) separate the colors of an organism's internal structure

D) magnify structures at various depths in a tissue

E) combine the images of the two objects that are very close together

A

Which of the following bacteria lack(s) a peptidoglycan cell wall?

A) Treponema pallidum

B) Mycobacterium tuberculosis

C) Mycoplasma pneumoniae

D) Staphylococcus aureus

E) These all contain a cell wall - they are all bacteria.

C

The microbial polymer that is composed of repeating subunits of N-Acetyl-muramic acid and N-Acetyl-glucosamine is:

A) the cytoplasmic membrane

B) the outer membrane of gram positive bacteria

C) the bacterial capsule

D) the archaea

E) peptidoglycan

E

Which of the following stains are considered differential?

A) capsule stain and gram stain

B) flagella stain and acid fast stain

C) acid fast stain and gram stain

D) acid fast stain and capsule stain

E) gram stain and flagella stain

C

The order of reagents in the Gram stain reaction is

A) safranin, alcohol, methylene blue, iodine

B) crystal violet, iodine, alcohol, safranin

C) methylene blue, alcohol, safranin, iodine

D) crystal violet, alcohol, iodine, safranin

E) alcohol, safranin, iodine, crystal violet

B

The major criteria used in placing bacteria into different groups is based on differences in

A) cell wall structure

B) cell membrane permeability

C) presence or absence of flagella

D) detergent susceptibility

E) presence or absence of cytoplasmic membrane

A

Which of the statements about immunofluorescence is not true?

A) uses fluorescently tagged molecules

B) makes use of the specificity in binding of antibodies

C) uses the dye methylene blue

D) would require a special UV microscope

E) stained cells often appear bright yellow-green against a black background

C

The cell wall of Gram-negative organisms

A) has a thick peptidoglycan layer AND is characterized by an outer membrane containing LPS.

B) has a thick peptidoglycan layer.

C) has a thin peptidoglycan layer AND is characterized by an outer membrane containing LPS.

D) has a thin peptidoglycan layer.

E) is more permeable to various molecules than the Gram-positive cell wall.

C

Penicillin would be most effective against

A) non-growing bacteria AND Gram-positive bacteria.

B) non-growing bacteria AND Gram-negative bacteria.

C) growing bacteria AND Gram-positive bacteria.

D) growing bacteria AND Gram-negative bacteria.

E) any actively growing bacteria.

C

The simplest technique for isolating bacteria in growth media is referred to as the

A) streak plate method

B) pour plate method

C) serial dilution method

D) MPN method

E) bacterial growth method

A

During which phase of growth are bacteria most susceptible to antibiotics?

A) lag

B) stationary

C) exponential (log)

D) decline

E) infection

C

During which phase of the bacterial growth curve does the total number of viable (live) cells decline?

A) stationary

B) lag

C) exponential

D) death

E) infection

D

A pure culture in exponential growth phase has a bacterial concentration of 6.4 x 108 cells/ml. If the bacterium has a generation time of 1 h, how long ago was the cell concentration 8.0 x 107 cells/ml?

A) 1 h

B) 2 h

C) 3 h

D) 4 h

E) 24 h

C

Generally, the enzymes of thermophiles

A) are more resistant to thermal denaturation.

B) react more efficiently with DNA.

C) are more readily denatured by heat.

D) have much greater activity than the enzymes of mesophiles

E) are larger than those of mesophiles

A

The optimal temperature for most human pathogens might be expected to range from

A) 20-45 degrees C

B) 35-40 degrees C

C) 15-24 degrees C

D) 93-98.6 degrees C

E) 35-40 degrees F

B

Organisms that require gaseous oxygen for metabolism are referred to as

A) facultative aerobes

B) obligate aerobes

C) facultative anaerobes

D) microaerobes

E) obligate anaerobes

B

The enzymes that deal with toxic oxygen-containing molecules is/are

A) glycolase AND superoxide dismutase.

B) superoxide dismutase AND cytochrome oxidase.

C) superoxide dismutase AND catalase.

D) catalase AND cytochrome oxidase.

E) cytochrome oxidase AND glycolase.

C

High concentrations of salt and sugar in foods

A) are useful in preserving the food AND tend to force water into a cell, causing plasmolysis

B) have no effect on water availability AND are useful in preserving the food.

C) are useful in preserving the food AND tend to draw water out of a cell

D) are useful in preserving the food AND force bacteria to divide

E) tend to force water into a cell, causing plasmolysis AND force bacteria to divide

C

Chemoheterotrophs

A) use sunlight as an energy source

B) use performed organic molecules as a carbon source

C) use performed organic molecules as an energy source

D) use inorganic chemicals as an energy source

E) use performed organic molecules as a carbon source AND as an energy source

E

A medium that inhibits the growth of organisms other than the one being sought is called a(n

A) synthetic medium

B) specific culture medium

C) selective medium

D) enrichment medium

E) differential medium

C

MacConkey agar is

A) a selective medium

B) a selective and differential medium

C) a differential medium

D) an enrichment medium

E) an anaerobic medium

B

The name given to the reaction involving addition of electrons or hydrogen atoms to a compound is

A) reduction

B) glycolysis

C) oxidation

D) metabolism

E) respiration

A

The most common starting pathway for the breakdown of sugars is

A) respiration

B) fermentation

C) oxidation

D) glycolysis

E) anabolism

D

Which of the following processes generates the greatest amount of energy?

A) fermentation

B) aerobic respiration

C) krebs cycle

D) glycolysis

E) phosphorylation

B

Enzymes speed up reactions by

A) raising activation energy

B) producing heat

C) reducing entropy

D) lowering activation energy

E) electron carriers

D

Most enzymes

A) are generic, typically recognizing a number of different substrates.

B) are specific, typically recognizing a single or a few substrates.

C) are active over a wide pH range.

D) are active over a wide temperature range.

E) are unaffected by heat or acidity.

B

What happens to the carbon molecules in the pyruvic acid that goes through the TCA cycle?

A) they get incorporated into cell material

B) they are excreted as waste organic acids

C) they become carbon dioxide

D) they form "energy storage molecules" for the cell

E) they become phosphorylated

C

Which may be or is an RNA molecule?

A) AGCCTAC and GGGCCCA

B) GGGCCCA and AAATTTA

C) GGGCCCA and GCCCUUA

D) GCCCUUA and AAATTTA

E) AGCCTAC and GGUCCCU

C

The lagging strand

A) is another name for any single-stranded DNA found in slowly dividing cells.

B) is formed during RNA replication because of the nature of the enzymes involved in it.

C) is formed during DNA replication because of the antiparallel nature of DNA.

D) is always the bottom strand of DNA or RNA during the replication process.

E) is always the upper strand of DNA or RNA during the replication process

C

Which is false about the RNA transcript?

A) it is formed using the DNA minus strand as a template

B) it has the same 5'-3' orientation as the DNA positive strand

C) it is made in short fragments that are then stitched together

D) the template starts at the promoter region

E) all the answers are false

C