Question 1

The cells wall of bacteria Z contains high concentrations of phospholipids along with proteins and relatively low amounts of lipopolysaccharide.When bacteria Z is gram stained, it will most like be colored?
A)Purple
B)Pink
C)Blue
D)Clear, it does not retain any stain

Accepted Answer

B

Question 2

The fungus Penicillium produces a compound that blocks peptidoglycan assembly.Why is a fungus trying to kill bacteria?
A)Fungi eat bacteria.
B)Fungi and bacteria are both decomposers and compete for resources.
C)The compound produced by the fungus is used for nitrogen fixation, the antibacterial properties are accidental.
D)The fungal compound is produced in response to a bacterial invasion of the fungal hyphae.

Accepted Answer

Fungi and bacteria are both decomposers and compete for resources, so it is possible that the fungus is producing the compound to gain an advantage in this competition.

Question 3

Are transformation and transduction the same process?
A)Yes; they both involve the acquisition of viral genes.
B)No; only transformation passes on genes for pathogenicity.
C)Yes; both processes transfer specific gene products to a specific bacterium.
D)No; although both involve gene transfer the sources of the genetic material differ.

Accepted Answer

Although both transformation and transduction involve the transfer of genetic material, transformation involves the uptake of free DNA from the environment whereas transduction involves the transfer of genetic material via a bacteriophage. Therefore, the sources of the genetic material are different.

Question 4

Irregular dental hygiene and a high sugar diet may led to tooth decay.Why?
A)Bacteria consume calcium.
B)Lactic acid fermentation is used to generate ATP under anaerobic conditions.
C)Plaque degrades the tooth's protective mucosal layers.
D)Glucose forms a weak acid when dissolved in saliva.

Accepted Answer

Bacteria in the mouth metabolize sugars and produce lactic acid as a byproduct, which can erode tooth enamel and lead to decay.

Question 5

A researcher observed a reduction in the number of chromosomes during cell division for a microbe, he concludes that the microbe must be
A)Eukaryotic
B)Prokaryotic
C)An archaean
D)a virus

Accepted Answer

Reduction in the number of chromosomes during cell division typically occurs in eukaryotic cells during meiosis. Prokaryotes, archaea, and viruses do not undergo meiosis in the same way, and do not typically show this reduction in chromosome number.

Question 6

Farmers often practice crop rotation to help enrich agricultural fields.Why are beans and other legumes often used in the rotations?
A)Beans fix nitrogen.
B)Bacteria in legume root nodules are nitrifiers.
C)Legumes enrich the soil by forming heterocysts.
D)Legumes remove toxins from the soil.

Accepted Answer

The answer of Farmers often practice crop rotation to help...

Question 7

Why is chlamydia much more common than syphilis?
A)Chlamydia is spread via droplet inhalation.
B)Syphilis can penetrate a condom whereas chlamydia cannot.
C)Many chlamydia infections are asymptomatic.
D)Chlamydia is viral, and viral diseases spread much quicker.

Accepted Answer

Chlamydia is often asymptomatic, meaning many people who have it do not show symptoms and unknowingly spread it to others, making it more common than syphilis.

Question 8

Genetic diversity in bacteria is created by mutation and __________.

Accepted Answer

The answer of Genetic diversity in bacteria is created by...

Question 9

An oil spill occurs, and Greg (a member of the clean up team) suggests adding fertilizer.Why is he making this suggestion?
A)The fertilizer encourages the growth of microbes that can break down the oil.
B)The chemicals in the fertilizer digest the oil residues.
C)The fertilizer interacts with the oil droplets and renders them harmless.
D)The fertilizer volitizes the oil.

Accepted Answer

Fertilizer contains nutrients that can promote the growth of naturally occurring microorganisms that can break down the oil. This process is known as bioremediation and is a common method used in oil spill clean up efforts.

Question 10

Many cells of the immune system have receptors that detect peptidoglycans and lipopolysaccharides.How do pathogenic bacteria avoid detection?
A)Pathogenic bacteria lack cell walls.
B)Pathogens often encase themselves in a gelatinous capsule.
C)Peptidoglycans are absent from pathogenic bacteria.
D)Disease is only possible if the immune system has been compromised by some other event.

Accepted Answer

Pathogenic bacteria can avoid detection by the immune system by encasing themselves in a gelatinous capsule. This capsule can make it difficult for immune cells to recognize and attack the bacteria, allowing them to evade the immune response and cause infection.

Question 11

Vibrio cholerae produces a toxin that destroys the intestinal epithelium.This leads to massive diarrhea; the diarrhea can kill the human via dehydration but helps the bacteria spread and colonize other humans.What is this relationship?
A)Mutualistic
B)Commensalistic
C)Symbiotic
D)Atavistic

Accepted Answer

The answer of Vibrio cholerae produces a toxin that destroys...

Question 12

A high concentration of chlorophyll imbedded in the plasma membrane fold of a newly discovered species of bacteria suggests a:
A)Chemolithoautotrophic metabolism
B)Chemoheterotrophic metabolism
C)Photoautotrophic metabolism
D)Photoheterotrophic metabolism

Accepted Answer

The high concentration of chlorophyll in the plasma membrane fold suggests that the bacteria are capable of photosynthesis, indicating a photoautotrophic metabolism, which is the ability to produce organic molecules using light energy and carbon dioxide as a carbon source.

Question 13

Bacteria typically use binary fission, but under special circumstances sexual reproduction is possible via horizontal gene transfer.

Accepted Answer

The answer of Bacteria typically use binary fission, but under...

Question 14

DNA replication and gene expression in archaeans more closely resemble eukaryotic cells than the same processes in bacteria.However both Bacteria and Archaea are prokaryotic.What does this suggest?
A)Eukaryotic cells are descended from modern Archaeans.
B)Bacterial cells are not related to Archaeans.
C)Eukaryotic cells shared a more recent common ancestor with Archaeans than with bacterial cells.
D)There must have been 2 origin events, one producing the bacteria and the other producing Archaeans and eukaryotic cells.

Accepted Answer

The fact that DNA replication and gene expression in archaeans more closely resemble eukaryotic cells than the same processes in bacteria suggests that eukaryotic cells shared a more recent common ancestor with Archaeans than with bacterial cells. This supports the hypothesis of the three-domain system, where Bacteria and Archaea are two separate domains of prokaryotes, and Eukarya is a separate domain of organisms that shared a common ancestor with Archaea.

Question 15

Genes abc and def have a high average cotransduction frequency.Genes abc and xyz have a very low average cotransduction frequency.What is the best explanation for this difference?
A)The genes abc and def are much closer to each other on the chromosome.
B)The genes abc and def must share a higher degree of sequence similarity.
C)Both genes have a high affinity for the viral binding sites.
D)Both genes code for gene products that are necessary for viral replication.

Accepted Answer

The high average cotransduction frequency suggests that genes abc and def are located close together on the chromosome, as they are more likely to be taken up together by the viral particle during transduction. The low cotransduction frequency for abc and xyz suggests that they are further apart on the chromosome and less likely to be taken up together during transduction.

Question 16

Current classification of prokaryotes is based on
A)morphology of flagella.
B)sequencing of proteins, DNA, and RNA.
C)occurrence of transverse binary fission.
D)type of colony formation.

Accepted Answer

Current classification of prokaryotes is based on sequencing of proteins, DNA, and RNA.

Question 17

If the label on a slide reads Gram-positive bacillus, what would a students expect to see?
A)Pink helical cells
B)Purple rod shaped cells
C)Red spherical cells
D)Blue coiled cells

Accepted Answer

Gram-positive bacteria have a thick peptidoglycan layer in their cell wall, which retains the crystal violet stain used in the Gram staining procedure, leading to purple-colored cells. Bacillus are rod-shaped bacteria.

Question 18

Phil has chronic ulcers, he has been taking acid blockers and drinking vast amounts of liquid antacids.These help relieve the symptoms but he still suffers from ulcers.What would be the best course of action to treat the source of his ulcers?
A)Taking several different antacids.
B)Increasing the dosage of acid blockers.
C)Taking a course of antibiotics.
D)Reducing the stress in his daily life.

Accepted Answer

Chronic ulcers are often caused by Helicobacter pylori infection, which can be treated with antibiotics to address the root cause rather than just alleviating symptoms.

Question 19

Early classification systems of the bacteria employed all of the following characteristics except
A)the ability to photosynthesize.
B)rRNA sequences.
C)motility.
D)colony or filament forming.

Accepted Answer

rRNA sequences were not used in early classification systems of bacteria.

Question 20

Why are children often told that if they eat too much candy their teeth will fall out?
A)Sugar attacks tooth enamel.
B)Sugars gradually replace the tooth enamel.
C)Bacteria use the sugar to make ATP.This fermentation process produces acids as a by-product.
D)Bacteria secrete acids in order to digest the sugar molecules.

Accepted Answer

The answer of Why are children often told that if...

Quiz 28: Prokaryotes

The cells wall of bacteria Z contains high concentrations of phospholipids along with proteins and relatively low amounts of lipopolysaccharide.When bacteria Z is gram stained, it will most like be colored?

The fungus Penicillium produces a compound that blocks peptidoglycan assembly.Why is a fungus trying to kill bacteria?

Are transformation and transduction the same process?

Irregular dental hygiene and a high sugar diet may led to tooth decay.Why?

A researcher observed a reduction in the number of chromosomes during cell division for a microbe, he concludes that the microbe must be

Farmers often practice crop rotation to help enrich agricultural fields.Why are beans and other legumes often used in the rotations?

Why is chlamydia much more common than syphilis?

Genetic diversity in bacteria is created by mutation and __________.

An oil spill occurs, and Greg (a member of the clean up team) suggests adding fertilizer.Why is he making this suggestion?

Many cells of the immune system have receptors that detect peptidoglycans and lipopolysaccharides.How do pathogenic bacteria avoid detection?

Vibrio cholerae produces a toxin that destroys the intestinal epithelium.This leads to massive diarrhea; the diarrhea can kill the human via dehydration but helps the bacteria spread and colonize other humans.What is this relationship?

A high concentration of chlorophyll imbedded in the plasma membrane fold of a newly discovered species of bacteria suggests a:

Bacteria typically use binary fission, but under special circumstances sexual reproduction is possible via horizontal gene transfer.

DNA replication and gene expression in archaeans more closely resemble eukaryotic cells than the same processes in bacteria.However both Bacteria and Archaea are prokaryotic.What does this suggest?

Genes abc and def have a high average cotransduction frequency.Genes abc and xyz have a very low average cotransduction frequency.What is the best explanation for this difference?

Current classification of prokaryotes is based on

If the label on a slide reads Gram-positive bacillus, what would a students expect to see?

Phil has chronic ulcers, he has been taking acid blockers and drinking vast amounts of liquid antacids.These help relieve the symptoms but he still suffers from ulcers.What would be the best course of action to treat the source of his ulcers?

Early classification systems of the bacteria employed all of the following characteristics except

Why are children often told that if they eat too much candy their teeth will fall out?