Micro Chapter 3

Which of the following is not true of bacteria?

A. Its DNA is not encased by a nuclear membrane.
B. It has a cell wall made of peptidoglycans and other distinctive chemicals.
C. It does not have membrane-bound organelles.
D. Its DNA is wrapped around histones.

D

2. The two main functions of bacterial appendages are …

A. attachment and protection.
B. attachment and motility.
C. motility and slime production.
D. energy reactions and synthesis. E. protection and motility.

B

Spirochetes have a unique twisting and flexing locomotion due to appendages called …

A. flagella.
B. cilia.
C. fimbriae.
D. periplasmic flagella (axial filaments).
E. sex pili.

D

A flagellum is anchored into the bacterial cell envelope by its …

A. hook.
B. outer membrane.
C. filament.
D. sheath.
E. basal body.

E

The term that refers to the presence of flagella over the entire perimeter of the cell surface is …

A. amphitrichous.
B. atrichous.
C. lophotrichous.
D. monotrichous.
E. peritrichous.

E

The flagellum of bacteria is a filament of the protein ________, but the flagellum of protozoa is composed of _____________.

A. tubulin / actin
B. flagellin / tubulin
C. actin / flagellin
D. pilin / tubulin

B

The term that refers to presence of flagella at both poles of a cell is …

A. amphitrichous.
B. atrichous.
C. lophotrichous.
D. monotrichous.
E. peritrichous.

A

Chemotaxis refers to the ability to …

A. move in response to light.
B. move in response to a chemical.
C. not move in response to a chemical.
D. transport desired molecules into cells.

B

A bacterial cell exhibiting chemotaxis probably has …

A. fimbriae.
B. a capsule.
C. thylakoids.
D. flagella.
E. metachromatic granules.

D

Movement of a cell toward a chemical stimulus is termed …

A. positive phototaxis.
B. negative phototaxis.
C. positive chemotaxis.
D. negative chemotaxis.
E. a tumble.

C

The short, numerous appendages used by some bacterial cells for adhering to surfaces are called …

A. flagella.
B. cilia.
C. fimbriae.
D. periplasmic flagella (axial filaments).
E. pili.

C

Which structure protects bacteria from being phagocytized by white blood cells?

A. cell wall
B. fimbriae
C. cell membrane
D. capsule
E. inclusion

D

The outcome of the Gram stain is based on differences in the cell’s:

A. ribosomes.
B. inclusions.
C. wall.
D. membrane
E. flagella.

C

Which order below reflects the correct procedure for Gram staining?

A. alcohol/acetone-crystal violet-safranin-iodine
B. crystal violet-alcohol/acetone-iodine-safranin
C. crystal violet-iodine-alcohol/acetone-safranin
D. iodine-safranin-crystal violet-alcohol/acetone
E. alcohol/acetone-safranin-crystal violet-iodine

C

During the Gram stain, __________ cells decolorize when the alcohol is applied.

A. Gram-positive
B. Gram-negative
C. both Gram positive and negative

B

If bacteria living in salty seawater were displaced to a freshwater environment, the cell structure that would prevent the cells from rupturing is the …

A. endospore.
B. cell wall.
C. cell membrane.
D. capsule.
E. slime layer.

B

Peptidoglycan is a unique macromolecule found in bacterial …
A. cell walls.
B. cell membranes.
C. capsules.
D. slime layers.
E. inclusions.

A

A bacterial cell wall that has primarily peptidoglycan with some amounts of teichoic acid and lipoteichoic acid is …

A. Gram-negative.
B. Gram-positive.
C. found in archaea.
D. a spheroplast.
E. acid-fast.

B

A bacterial genus that has waxy mycolic acid in the cell wall is …

A. Mycobacterium.
B. Mycoplasma.
C. Streptococcus.
D. Corynebacterium.
E. Salmonella.

A

The difference in cell wall structure of Mycobacterium and Nocardia compared to the typical Gram- positive bacterial cell wall structure is …

A. more peptidoglycan.
B. predominance of unique, waxy lipids.
C. easily decolorized.
D. presence of lipopolysaccharide.
E. All of the choices are correct.

B

The _____ stain is used to stain and differentiate Mycobacterium and Nocardia from other bacteria.

A. acid-fast
B. methylene blue
C. Gram
D. negative
E. basic

A

The enzyme _____, found in tears and saliva, can hydrolyze the bonds in the glycan chains of bacterial cell walls.

A. penicillinase
B. lysozyme
C. peptidase
D. All of the choices are correct.
E. None of the choices is correct.

B

Lysozyme is most effective against …

A. Gram-negative organisms.
B. Gram-positive organisms.
C. mycoplasmas.
D. cyanobacteria.
E. archaea.

B

All of the following structures contribute to the ability of pathogenic bacteria to cause disease except the …

A. inclusions.
B. fimbriae.
C. capsule.
D. slime layer.
E. outer membrane of Gram-negative cell walls.

A

Which of the following does not pertain to the classical endotoxin LPS?

A. is a specific cell wall lipid
B. can stimulate fever in the human body
C. can cause septic shock in the human body
D. is involved in typhoid fever and some meningitis cases E. is found in acid-fast bacterial cell walls

E

The site(s) for most ATP synthesis in bacterial cells is(are) the …

A. ribosomes.
B. mitochondria.
C. cell wall.
D. inclusions.
E. cell membrane.

E

Gram-negative bacteria …

A. are more susceptible to antibiotics that target peptidoglycan than Gram-positive organisms.
B. are less susceptible to antibiotics that target peptidoglycan than Gram-positive organisms.
C. stain purple in the Gram stain.
D. encompass all pathogens.

B

The peptidoglycan found in bacterial cell walls invariably consists of polysaccharide chains composed of repeats of the disaccharide ___________, further connected to one another through peptide cross bridges.

A. Glucose – Galactose
B. Mannose – Sialic acid
C. N-acetylglucosamine – N-acetylalosaminuronic acid
D. N-acetylglucosamine – N-acetylmuramic acid
E. Glucosamine – Galactosamine

D

All bacterial cells have …

A. one or more chromosomes.
B. one or more fimbriae.
C. the ability to produce endospores.
D. capsules.
E. flagella.

A

The most immediate result of destruction of a cell’s ribosomes would be …

A. material would not be able to cross the cell membrane. B. protein synthesis would stop.
C. destruction of the cell’s DNA.
D. formation of glycogen inclusions.
E. loss of capsule.

B

The bacterial chromosome …
A. is located in the cell membrane.
B. contains all the cell’s plasmids.
C. is part of the nucleoid.
D. forms a single linear strand of DNA.
E. All of the choices are correct.

C

Which of the following is mismatched?

A. ribosomes – protein synthesis
B. inclusions – excess cell nutrients and materials
C. plasmids – carry genes essential for growth and metabolism
D. nucleoid – hereditary material
E. cytoplasm – dense, gelatinous solution

C

Plasmids …

A. are found in all bacteria.
B. are essential for growth and metabolism.
C. cannot be passed between organisms.
D. cannot be passed on to progeny.
E. are often the site of pathogenic genes.

E

The chemical components of ribosomes are proteins and …

A. mRNA.
B. tRNA.
C. rRNA.
D. All of the choices are correct.
E. None of the choices is correct.

C

The function of bacterial endospores is …

A. to convert gaseous nitrogen to a usable form for plants. B. reproduction and growth.
C. protection of genetic material during harsh conditions. D. storage of excess cell materials.
E. to act as sites for photosynthesis.

C

Chemical analysis of a bacterial cell structure detects calcium and dipicolinic acid. What is the identity of this structure?

A. cell wall
B. capsule
C. slime layer
D. nucleoid
E. endospore

E

Cells form a _____ arrangement when cells in a chain snap back upon each other forming a row of cells oriented side by side.

A. tetrad
B. strep
C. staph
D. sarcina
E. palisade

E

Endospores are …

A. metabolically inactive.
B. resistant to heat and chemical destruction.
C. resistant to destruction by radiation.
D. living structures.
E. All of the choices are correct.

E

Bacterial endospores are not produced by …

A. Staphylococcus.
B. Sporosarcina.
C. Bacillus.
D. Clostridium.

A

39. Which term is not used to describe bacterial cell shapes?

A. coccus
B. tetrad
C. vibrio
D. rod
E. spirochete

B

If you looked at a _________ under the microscope, you would likely see an irregular cluster of spherical cells.

A. palisade
B. sarcina
C. staphylococcus
D. streptococcus
E. diplococcus

C

A chain of rod-shaped cells would be called a(an) …

A. streptobacillus.
B. staphylobacillus.
C. streptococcus.
D. staphylococcus.
E. palisades.

A

_____ Manual of Systematic Bacteriology is a manual of bacterial descriptions and classifications.

A. Pasteur’s
B. Lister’s
C. Bergey’s
D. Leeuwenhoek’s
E. Koch’s

C

Which of the following is not a phenotypic trait of bacteria?

A. rRNA sequencing
B. shape
C. growth pattern in a culture medium
D. biochemical reaction

A

A client has a serious case of the flu. A random sample of sputum was taken from the patient coughing up blood. The lab tech said they had isolated a bacterium that did not have any peptidoglycan. You hypothesize that the identity of this microbe could possibly be …

A. Mycobacterium tuberculosis.
B. Borrelia burghdorferi.
C. Streptococcus pneumoniae.
D. Mycoplasma pneumoniae.
E. Staphylococcus aureus.

D

T/F
Archaea do not have the typical peptidoglycan structure found in bacterial cell walls.

T

T/F
Cellular organisms without a true nucleus include bacteria and viruses.

F

T/F
The flagella of bacteria move in a whip-like motion

F

T/F
The slime layer provides bacteria greater pathogenicity as compared to the capsule.

F

T/F
If during the Gram stain procedure, the bacterial cells were viewed immediately after crystal violet was applied, Gram-positive cells would be purple but Gram-negative cells would be colorless.

F

T/F
Iodine is the decolorizer in the Gram stain.

F

T/F
The cell envelope of Gram-positive bacteria has two layers: a thick cell wall and the cell membrane.

T

T/F
Gram-negative bacteria do not have peptidoglycan in their cell walls.

F

T/F
The bacterial cell membrane is a site for many enzymes and metabolic reactions.

T

T/F
If you observe rod-shaped, pink cells on a slide that had just been Gram-stained, you can assume that their cell walls contain endotoxin.

T

T/F
Both Gram-positive and Gram-negative cells have outer membranes.

F

T/F
Alcohol-based compounds can weaken the outer membrane of Gram-negative bacteria.

T

T/F
Bacteria have a cytoskeleton of protein polymers to help maintain their shape.

T

T/F
Endospores of certain bacterial species can enter tissues in the human body, germinate, and cause an infectious disease.

T

T/F
Boiling water (100°C) can normally destroy all endospores.

F

A 3-year-old patient is admitted to the ER after a sudden onset of high fever and chills, a productive cough, and shortness of breath. The parents indicate that the child had been healthy up until a few hours ago. An initial workup of the child shows an elevated temperature (103°F), a rapid pulse rate (140 bpm), and a low oxygen saturation level (82%). Supplemental oxygen and acetaminophen are administered immediately, and specimens are obtained from the patient for microbial analysis.

1. The specimens are Gram-stained and analyzed microscopically. The laboratory technician observes spherical purple-colored cells arranged in short chains. Based upon this evidence, which of the following microbes is most likely the pathogen affecting the patient?

A. Bacillus cereus
B. Vibrio cholerae
C. Staphylococcus aureus
D. Streptococcus pneumoniae

D

Further microscopic analysis reveals a pronounced clearing around each of the spherical cells against a dark background. This clearing indicates that the pathogen possesses which structure(s)?
A. endospores B. a capsule C. a nucleoid D. pili

B

You head back to the patient’s room to inform the family of the child’s condition. In educating the parents about the pathogen, which of the following statements would you use to correctly describe the medical importance of a bacterial capsule?

A. A capsule is less dense and thick, and bound more loosely to a cell than a slime layer.
B. A capsule allows for the production of dry, wrinkly colonies when encapsulated bacteria are
grown on solid agar.
C. A capsule decreases a bacterium’s pathogenicity.
D. A capsule can protect a bacterium from the phagocytic activities of white blood cells,
enhancing its ability to cause disease.

D

As a triage nurse in the ER, you begin the assessment of an elderly patient complaining of bloody diarrhea and severe stomach cramps. You find the patient has a fever of 104°F as well, and is showing signs of dehydration. IV fluids are administered while further analysis of the patient continues.

4. Specimen collection from the patient is ordered for microbial analysis in the hospital laboratory. Based upon the patient’s symptoms, which of the following is most correct regarding this process?

A. You will aseptically obtain cerebrospinal fluid for analysis.
B. You will obtain a clean catch urine sample for analysis.
C. You will obtain a stool sample for analysis.
D. You will aseptically obtain a throat swab for analysis.

C

Testing is performed on the specimen in the laboratory. The Gram stain is an important test, as it differentiates bacteria into two broad classes: Gram positive and Gram negative. Which step in this process is the differential step, for it only acts upon one type of cell?

A. the addition of Gram’s iodine (mordant)
B. the addition of crystal violet
C. the decolorization with alcohol
D. the addition of safranin (counterstain)

C

Gram staining reveals the presence of Gram-negative bacilli in the patient’s stool. Thinking about the patient’s spike in temperature, you understand now how this bacterium could cause a fever. Which of the following is the correct explanation?

A. Gram-negative bacteria have a thick peptidoglycan layer which confers their ability to cause fever.
B. Gram-negative bacteria have two periplasmic spaces which enhance their ability to cause fever.
C. Gram-negative bacteria have porin proteins in their outer membrane which confer their ability to
cause fever.
D. Gram-negative bacteria have lipopolysaccharide in their outer membrane, and the lipid portion
confers their ability to cause fever.

D

Based upon the information you have received from the laboratory, you inform the patient of his condition. In doing so, you tell him that this infection may be difficult to treat with antibiotics. Which part of the cell envelope restricts the passage of many of these drugs into gram-negative bacteria?

A. peptidoglycan
B. cell membrane
C. outer membrane layer
D. lipoteichoic acids

C