Chapter 1 Test

Which of the following environmental factors influence the growth of bacteria in the laboratory? a. all of the above b. gaseous composition of the atmosphere c. temperature d. pH

a. all of the above (gaseous composition of the atmosphere, temperature, pH)

The laboratory receives a specimen in which the doctor suspects that the infecting organism is Haemophilus influenzae. This organism grows best in an atmosphere that contains 5% to 10% carbon dioxide. It is therefore classified as what type of bacteria? a. capnophilic b. obligate aerobe c. obligate anaerobe d. facultative anaerobe

a. capnophilic

The three basic shapes of bacteria include all the following, except a. cell wall deficient b. spirochetes c. cocci d. bacilli

a. cell wall deficient

A _____ is a single, closed, circular piece of DNA that is supercoiled to fit inside a bacterial cell. a. chromosome b. transposon c. frame-shift mutation d. phenotype

a. chromosome

Which is a biochemical process carried out by both obligate and facultative anaerobes? a. fermentation b. oxidation c. respiration d. reduction

a. fermentation

The outer cell wall of the gram-negative bacteria serves three important functions, which includes all the following, except: a. it provides an attachment site for the flagella, which will act in locomotion b. it acts as a barrier to hydrophobic compounds and harmful substances c. it provides attachment sites that enhance adhesion to host cells d. it acts as a sieve

a. it provides an attachment site for the flagella, which will act in locomotion

When performing a Gram stain on a gram-negative organism, the crystal violet is absorbed into this outer cell wall layer, and then washed away with the acetone alcohol. What is the main component of the outer layer of the cell wall? a. lipopolysaccharide b. mycolic acid c. peptidoglycan d. n-acetyl-D-muramic acid

a. lipopolysaccharide

What type of fermentation produces lactic, acetic, succinic, and formic acids as the end products? a. mixed acid b. homolactic c. butanediol d. propionic

a. mixed acid

This constituent of a gram-positive cell wall absorbs crystal violet but is not dissolved by alcohol, thus giving the gram-positive cell its characteristic purple color. a. peptidoglycan b. carbolfuchsin c. cholesterol d. mycolic acid

a. peptidoglycan

What structure is described as a phospholipid bilayer embedded with proteins and sterols that regulates the type and amount of chemicals that pass in and out of a cell? a. plasma membrane b. endoplasmic reticulum c. cell wall d. mitochondria

a. plasma membrane

Genes that code for antibiotic resistance are often found on small, circular pieces of DNA. These DNA pieces are called a. plasmids b. genomes c. chromosomes d. phenotypes

a. plasmids

The function of a cell wall is to a. provide rigidity and strength to the exterior of the cell b. protect the eukaryote from predators c. provide reserve energy to the eukaryotic cell d. regulate the transport of macromolecules in and out of the cell

a. provide rigidity and strength to the exterior of the cell

These are enzymes that cut the bacterial DNA at specific locations. a. restriction enzymes b. temperate lysogeny enzymes c. bacteriophage enzymes d. conjugation enzymes

a. restriction enzymes

Bacterial species that exhibit phenotypic differences are considered a. subspecies b. biovarieties c. serovarieties d. phagevarieties

a. subspecies

All of the following statements are true about viruses, except: a. viruses do not need host cells to survive and grow b. viruses are acellular but are surrounded by a protein coat c. viruses consist of DNA or RNA but not both d. viruses can infect bacteria, plants, and animals

a. viruses do not need host cells to survive and grow

Who was considered the father of protozoology and bacteriology? a. Carl Landsteiner b. Anton van Leeuwenhoek c. Louis Pasteur d. Michael Douglas

b. Anton van Leeuwenhoek

In what staining procedure does carbolfuchsin penetrate the bacterial cell wall through heat or detergent treatment? a. acridine orange stain b. acid-fast stain c. endospore stain d. gram stain

b. acid-fast stain

What is the purpose of a capsule? a. prevent osmotic rupture of the cell membrane b. act as a virulence factor in helping the pathogen evade phagocytosis c. make up the periplasmic space d. provide an attachment site for somatic antigens

b. act as a virulence factor in helping the pathogen evade phagocytosis

What class of organisms, such as the Streptococcus sp., can survive in the presence of oxygen but do not use oxygen in its metabolic processes? a. facultative anaerobe b. aerotolerant anaerobe c. obligate anaerobe d. microaerophilic

b. aerotolerant anaerobe

A microorganism that is a unicellular organism and lacks a nuclear membrane and true nucleus belongs to which classification? a. algae b. bacteria c. parasite d. fungi

b. bacteria

To survive, microbial inhabitants have learned to adapt by varying all of the following, except a. growth at particular temperatures b. bacterial shape c. growth in all atmospheric conditions d. growth rate

b. bacterial shape

What stain is used for medically important fungi? a. methylene blue b. lactophenol cotton blue c. acridine orange d. acid-fast

b. lactophenol cotton blue

In the medical microbiology laboratory, the ability of a gram-negative bacterium to ferment this sugar is the first step in its identification. a. mannitol b. lactose c. sucrose d. trehalose

b. lactose

This form of DNA is commonly found in eukaryotic cells. a. colloid b. linear c. circular d. plasmid

b. linear

Diagnostic microbiologists apply placement and naming of bacterial organisms into all the following categories, except a. family b. order c. species d. genus

b. order

What process involves transferring or exchanging genes between similar regions on two separate DNA molecules? a. IS element b. recombination c. transcription d. replication

b. recombination

What makes the interior of the plasma membrane potentially impermeable to water-soluble molecules? a. the ion channels are found there b. the hydrophobic tails of the phospholipid molecules are found there c. the hydrophilic tails of the phospholipid molecules are found there d. the cholesterol molecules in the plasma membrane are found solely in the interior of the membrane

b. the hydrophobic tails of the phospholipid molecules are found there

Diphtheria is a disease produced by Corynebacterium diphtheriae. However, not all C. diphtheriae bacteria produce the toxin that causes this disease. To produce the toxin, the bacteria must first become infected with a bacteriophage. The process by which bacterial genes are transferred to new bacteria by the bacteriophage is called a. transformation b. transduction c. replication d. conjugation

b. transduction

What enables the microbiologist to select the correct media for primary culture and optimize the chance of isolating a pathogenic organism? a. understanding the cell structure and biochemical pathways of an organism b. understanding the growth requirements of potential pathogens at specific body site c. knowing the differences in cell walls of particular bacteria d. determining staining characteristics

b. understanding the growth requirements of potential pathogens at specific body site

If bacteria utilize various carbohydrates for growth, they are usually detected by a. production of carbon dioxide b. production of keto acids c. acid production and change of color from the pH indicator d. alkaline production and change of color from the pH indicator

c. acid production and change of color from the pH indicator

The following describes the log phase of bacterial growth: a. limited nutrients with bacteria count remaining constant b. number of nonviable bacterial cells exceeds the number of viable cells c. bacteria doubling with each generation time d. preparing to divide

c. bacteria doubling with each generation time

Name the numerous short (3 to 10 μm) projections that extend from the cell surface and are used for cellular locomotion. a. phospholipid b. mitochondria c. cilia d. flagella

c. cilia

The Gram stain is a routine stain used in bacteriology to determine gram-positive and gram-negative bacteria based on the a. phenotypic characteristics of the organism b. composition of the bacterial pili c. composition of the bacterial cell wall d. composition of the bacterial cell membrane

c. composition of the bacterial cell wall

A microbiology technologist performs a traditional bacterial stain on a colony from a wound culture that is suspected to contain bacteria from the genus Clostridium. The unstained areas in the bacterial cell observed by the technologist are called a. cilia b. mitochondria c. endospores d. ribosomes

c. endospores

Diagnostic schemes in the microbiology laboratory typically analyze each unknown bacterium's metabolic processes for all the following, except a. production of specific end products from specific substrates b. production of an acid or alkaline pH in the test medium c. energy utilization for metabolic processes d. utilization of a variety of substrates as carbon sources

c. energy utilization for metabolic processes

All the following are types of media, except a. differential b. selective c. fastidious d. transport

c. fastidious

A clinical laboratory scientist is working on the bench, reading plates, and notices that a culture has both a unicellular form and a filamentous form. What type of organism exhibits these forms? a. virus b. parasite c. fungi d. bacteria

c. fungi

The nuclear membrane in prokaryotes is a. a classic membrane b. impenetrable c. missing d. a lipid bilayer membrane

c. missing

Which of these bacteria cannot grow in the presence of oxygen? a. facultative anaerobes b. capnophilic organisms c. obligate anaerobe d. obligate aerobes

c. obligate anaerobe

Prokaryotic cells have which of the following structures in their cytoplasm? a. golgi apparatus b. endoplasmic reticulum c. ribosomes d. mitochondria

c. ribosomes

In the laboratory, the clinical microbiologist is responsible for all the following, except a. isolating microorganisms b. identifying microorganisms c. selecting treatment for patients d. analyzing bacteria that cause disease

c. selecting treatment for patients

A microbiologist is working with two separate cultures of the same organism. The bacteria in one culture are resistant to penicillin, whereas the bacteria in the other culture are susceptible to penicillin. The bacteria from both cultures are mixed together, and all the resulting bacteria are resistant to penicillin. What caused this phenomenon? a. a frame-shift mutation occurred that allowed the susceptible population of bacteria to develop resistance to penicillin b. the plasmid carrying the susceptibility gene was transferred to the resistant population of bacteria c. the plasmid carrying the resistance gene was transferred to the susceptible population of bacteria d. an IS element was inserted into the genome of the susceptible bacterial population

c. the plasmid carrying the resistance gene was transferred to the susceptible population of bacteria

Some bacteria grow at 25° C or 42° C, but diagnostic laboratories routinely grow pathogenic bacteria at what temperature? a. 10° C b. 30° C c. 60° C d. 35° C

d. 35° C

Lysogeny occurs when a. competent bacteria cells take up naked DNA b. genes present in the IS element are expressed in the bacterial cell c. genetic material is transferred from one bacterium to another through a sex pilus d. genes present in the bacteriophage DNA are incorporated into the bacteria's genome

d. genes present in the bacteriophage DNA are incorporated into the bacteria's genome

Mycobacteria have a gram-positive cell wall structure with a waxy layer containing these two compounds. a. mycolic acid and lipopolysaccharides b. glycolipids and phospholipids c. lipopolysaccharides and phospholipids d. glycolipids and mycolic acid

d. glycolipids and mycolic acid

The three regions of the lipopolysaccharide include all the following, except a. antigenic O-specific polysaccharide b. endotoxin (inner lipid A) c. core polysaccharide d. mycolic acid

d. mycolic acid

Mycoplasma and Ureaplasma spp. must have media supplemented with serum or sugar as nutrients and because a. their cell walls contain detoxifying enzymes b. the sterols in their cell walls are soluble in normal bacterial media c. their cell walls contain only peptidoglycan d. they lack cell walls

d. they lack cell walls