Microbiology Test 1

1) Microorganisms are involved in each of the following processes EXCEPT
A) infection.
B) decomposition of organic material.
C) O2 production.
D) food production.
E) smog production

E. smog production

2) Each of the following organisms would be considered a microbe EXCEPT
A) yeast.
B) protozoan.
C) bacterium.
D) mushroom.
E) virus

d. mushroom

3) The term used to describe a disease-causing microorganism is
A) microbe.
B) bacterium.
C) virus.
D) pathogen.
E) infection.

d. pathogen

4) Common commercial benefits of microorganisms include synthesis of
A) antibiotics.
B) aspirin.
C) insulin.
D) antibiotics and aspirin.
E) antibiotics and insulin.

e. antibiotics and insulin

5) Commercial utilization of microbial products has become increasingly popular due to their environmentally friendly
nature. Removal of these products from the environment typically utilizes
A) enzymes.
B) organic acids.
C) organic solvents.
D) soap.
E) alcohol

a. enzymes

6) The formal system for classifying and naming organisms was developed by
A) Robert Koch.
B) Ignaz Semmelweis.
C) Aristotle.
D) Carolus Linnaeus.
E) Louis Pasteur

d. carolus Linnaeus

7) In the name Staphylococcus aureus, aureus is the
A) genus.
B) domain name.
C) specific name.
D) kingdom.
E) family name

c. specific name

8) A prokaryotic cell may possess each of the following cellular components EXCEPT
A) flagella.
B) a nucleus.
C) ribosomes.
D) a cell wall.
E) a cell membrane

b. a nucleus

9. which of the following is NOT associated with viruses?

   a. organells

   b. nucleic acid

   c. envelope

   d. spikes

   e. capsid

a. organelles

1) Protozoan motility structures include
A) cilia.
B) flagella.
C) pseudopods.
D) cilia and pseudopods only.
E) cilia, flagella, and pseudopods.

e. cilia, flagella, and pseudopods.

12) Viruses are not considered living organisms because they
A) cannot reproduce by themselves.
B) are structurally very simple.
C) can only be visualized using an electron microscope.
D) typically associated with disease.
E) are ubiquitous in nature.

a. cannot reproduce by themselves

13) The infectious agent that causes AIDS is a
A) virus.
B) bacterium.
C) yeast.
D) protozoan.
E) mold

a. virus

14) Which of the following is NOT a domain in the three-domain system?
A) animalia
B) archaea
C) bacteria
D) eukarya

a. animalia

15) Classification of organisms into three domains is based on
A) the presence of a cell wall.
B) the number of cells in the organism.
C) cellular organization.
D) nutritional requirements.
E) cellular proteins.

c. cellular organization

16) Archaea differ from bacteria in that archaea
A) have diverse cell wall compositions.
B) lack nuclei.
C) use organic compounds for food.
D) reproduce by binary fission.
E) are prokaryotic.

a. have diverse cell wall compositions

7) Who is credited with first observing cells?
A) Robert Hooke
B) Anton van Leeuwenhoek
C) Robert Koch
D) Louis Pasteur
E) Carolus Linnaeus

a. Robert hooke

18) Who is credited with first observing microorganisms?
A) Robert Hooke
B) Anton van Leeuwenhoek
C) Robert Koch
D) Louis Pasteur
E) Carolus Linnaeus

b. anton van leeuwenhoek

19) Biogenesis refers to the
A) spontaneous generation of organisms from nonliving matter.
B) development of life forms from preexisting life forms.
C) development of aseptic technique.
D) germ theory of disease

b. development of life forms from preexisting life forms

20) If you were setting up an experiment to disprove spontaneous generation in a liquid medium, which of the following
would be essential to the experiment?
A) supplying the liquid with nutrients
B) starting with a liquid that contains microorganisms
C) adding antibiotics to the liquid
D) using a sterile liquid and eliminating exposure to microorganisms
E) adding carbon dioxide to the liquid

d. using a sterile liquid and eliminating exposure to microorganisms

21) The arguments supporting spontaneous generation were finally disproved by
A) Louis Pasteur.
B) Francesco Redi.
C) Rudolf Virchow.
D) John Needham.
E) Lazzaro Spallanzani

a. Louis pasteur

22) Regarding Louis Pasteur’s experiments with the S-neck flask, which of the following statements is TRUE?
A) Air exchange was involved.
B) A food source was provided.
C) The possibility of contamination was removed.
D) All preexisting microorganisms were killed.
E) All of the answers are correct

e. all of the answers are correct

23) The microbial process of converting sugars to alcohol is known as
A) fermentation.
B) pasteurization.
C) tyndallization.
D) lyophilization.
E) alcoholism.

a. fermentation

24) Proof that a microbe could cause disease was provided by
A) Pasteur.
B) Lister.
C) Koch.
D) Wasserman.
E) Semmelweis

c. koch

25) The use of phenol (carbolic acid) as a wound disinfectant was first practiced by
A) Lister.
B) Semmelweis.
C) Pasteur.
D) Holmes.
E) Koch

a. lister

26) Mycology is the study of
A) mycoplasma.
B) mushrooms.
C) protozoa.
D) molds.
E) molds, yeast, and mushrooms

e. molds, yeast, and mushrooms

27) The first step for directly linking a microbe to a specific disease according to Koch’s postulates is to
A) culture the blood or other body fluid from a diseased animal using nutrient medium.
B) inject a sample of blood or other body fluid from a diseased animal into a healthy animal.
C) obtain a sample of blood or other body fluid from a diseased animal.
D) compare the blood of a sick animal to blood obtained from a healthy animal.

E) isolate microbes from the blood of healthy animals.

c. obtain a sample of blood or other body fluid from a diseased animal

28) In which of the following situations would Koch’s postulates be utilized?
A) determination of the cause of a patient’s illness in a hospital microbiology lab
B) development of a new antibiotic in a pharmaceutical lab
C) determination of the cause of cancer in a patient
D) formulation of a vaccine against a new pathogen in a genetic engineering lab
E) whenever the scientific method is used to investigate a microbiological problem

a. determination of the cause of a patient’s illness in a hospital mirobiology lab

29) Robert Koch identified the cause of
A) smallpox.
B) anthrax.
C) diphtheria.
D) AIDS.
E) tuberculosis

b. anthrax

30) ________ is the physician first associated with vaccination.
A) Pasteur
B) Jenner
C) Lister
D) Koch
E) Escherich

b. jenner

1) Which of the following findings was essential for Edward Jenner’s vaccination process?
A) Exposure to a milder disease form may produce immunity.
B) A weakened microorganism will not cause disease.
C) Someone who recovers from a disease will not acquire that disease again.
D) Disease is caused by viruses.
E) Pathogenic microorganisms infect all humans and animals in the same manner.

a. exposure to a milder disease form may produce immunity

32) Antibiotics are produced by
A) viruses.
B) bacteria.
C) protozoa.
D) fungi.
E) bacteria and fungi.

e. bacteria and fungi

33) The first antibiotic to be utilized was
A) salvarsan.
B) vancomycin.
C) penicillin.
D) sulfonamides.
E) quinine

c. penicillin

34) Who was the first scientist to pursue a “magic bullet” that could be used to treat infectious disease?
A) Jenner
B) Pasteur
C) Ehrlich
D) Lister
E) Semmelweis

c. lister

35) Fungal infections are studied by
A) virologists.
B) bacteriologists.
C) parasitologists.
D) mycologists.
E) herpetologists

d. mycologists

36) Vaccinations are available for all of the following diseases EXCEPT
A) measles.
B) rubella.

c. mumps.

d. strep throat

e. hepatitis B.

d. strep throat

37) Recombinant DNA refers to the
A) study of bacterial ribosomes.
B) study of the function of genes.
C) interaction between human and bacterial cells.
D) synthesis of proteins from genes.
E) DNA resulting when bacterial genes are inserted in an animal genome

E. DNA resulting when bacterial genes are inserted in an animal genome

38) Molecular biology is the study of
A) DNA synthesis.
B) RNA replication.
C) protein synthesis.
D) enzyme function.
E) the structure and function of macromolecules essential to life.

e. the structure and function of macromolecules essential to life

39) Microorganisms are essential to our life. Each of the following is an example of a beneficial function of microorganisms
EXCEPT
A) alternative fuel production.
B) bioremediation.
C) gene therapy.
D) agriculture.
E) increased morbidity

e. increased morbidity

40) The major food producers for other living organisms is/are
A) higher plants.
B) cyanobacteria.
C) algae.
D) higher plants and algae.
E) higher plants, cyanobacteria, and algae

e. higher plants, cyanobacteria, and algae

41) Gene therapy is currently used to treat all of the following diseases EXCEPT
A) severe combined immunodeficiency disease (SCID).
B) Duchenne’s muscular dystrophy.
C) cystic fibrosis.
D) LDL-receptor deficiency.
E) colon cancer

e. colon cancer

42) Recombinant DNA technology has become an increasingly important part of our life. It is used for all of the following
EXCEPT
A) vaccine production.
B) enhancing food longevity.
C) synthesis of water.
D) drug production.
E) increasing the nutritional value of food

c. synthesis of water

43) Normal microbiota are typically found in and on all the following body locations EXCEPT the
A) skin.
B) mouth.
C) colon.
D) blood.
E) upper respiratory system

d. blood

44) Which of the following statements about biofilms is FALSE?
A) Compared to free-living bacteria, biofilms are more sensitive to antibiotics.
B) Biofilms in pipes can block the flow of water.
C) Biofilms in your body protect mucous membranes from harmful microbes.
D) Biofilms on medical devices cause infections.
E) Biofilms on rocks provide food for animal life.

a. compared to free-living bacteria, biofilms are more sensitive to antibiotics

45) Development of emerging infectious disease can be a result of all of the following EXCEPT
A) microbial mutation.
B) modern transportation.
C) use of genetically modified foods.
D) changes in the environment.
E) overuse of antibiotics

c. use of genetically modified foods

1) Which of the following statements about the atom C is FALSE?
A) It has 6 protons in its nucleus.
B) It has 12 neutrons in its nucleus.
C) It has 6 electrons orbiting the nucleus.
D) Its atomic number is 6.
E) Its atomic weight is 12.

b. it has 12 neutrons in its nucleus

3) Antacids neutralize acid by the following reaction. Identify the salt in the following equation:
Mg(OH)2 + 2HCl → MgCl2 + H2O
A) Mg(OH)2
B) HCl
C) MgCl2
D) H2O
E) None of the answers is correct

c. MgCl2

4) Which of the following statements is FALSE?
A) Salts readily dissolve in water.
B) Water molecules are formed by hydrolysis.
C) Water freezes from the top down.
D) Water is a part of a dehydration synthesis reaction.
E) Water is a polar molecule.

b. water molecules are formed by hydrolysis

5) Which of the following is the type of bond holding K+ and I- ions in KI?
A) ionic bond
B) covalent bond
C) hydrogen bond

a. ionic bond

6) Which of the following is the type of bond between molecules of water in a beaker of water?
A) ionic bond
B) covalent bond
C) hydrogen bond

c. hydrogen bond

7) What is the type of bond holding hydrogen and oxygen atoms in the H2O molecule?
A) ionic bond
B) covalent bond
C) hydrogen bond

b. covalent bond

8) Identify the following reaction: Glucose + Fructose → Sucrose + Water
A) dehydration synthesis reaction
B) hydrolysis reaction
C) exchange reaction
D) reversible reaction
E) ionic reaction

a. dehydration synthesis reaction

9) Identify the following reaction: Lactose + H2O → Glucose + Galactose
A) dehydration synthesis reaction
B) hydrolysis reaction
C) exchange reaction
D) reversible reaction
E) ionic reaction

b. hydrolysis reaction

10) Identify the following reaction: HCl + NaHCO3 → NaCl + H2CO3
A) dehydration synthesis reaction
B) hydrolysis reaction
C) exchange reaction
D) reversible reaction
E) ionic reaction

c. exchange reaction

11) Identify the following reaction: NH4OH ⇌ NH3 + H2O
A) dehydration synthesis reaction
B) hydrolysis reaction
C) exchange reaction
D) reversible reaction
E) ionic reaction

d. reversible reaction

12) Which type of molecule contains the alcohol glycerol?
A) carbohydrate
B) phospholipids
C) DNA
D) protein

b. phospholipids

13) Which type of molecule is composed of (CH2O) units?
A) carbohydrate
B) lipid
C) nucleic acid
D) protein

a. carbohydrates

14) Which type of molecule contains -NH2 groups?
A) carbohydrate
B) triglycerides
C) nucleic acid
D) protein

d. protein

15) Which type of molecule NEVER contains a phosphate group?
A) triglycerides
B) lipid
C) nucleic acid
D) ATP

a. triglycerides

16) Based upon the valence numbers of the elements magnesium (2) and hydrogen (1), predict how many covalent bonds
would form between these atoms to achieve the full complement of electrons in their outermost energy shells.
A) one
B) two
C) three
D) four

b. two

18) Which of the following statements regarding protein structure is FALSE?
A) The primary structure is formed by covalent bonding between amino acid subunits.
B) Secondary structures are formed only from hydrogen bonds.
C) Tertiary structures are formed only from covalent bonds.
D) Quaternary structures involved multiple polypeptides.

c. tertiary structures are formed only from covalent bonds

19) Which of the following pairs is mismatched?
A) NaOH ⇌ Na+ + OH- — base
B) HF ⇌ H+ + F- — acid
C) MgSO4 ⇌ Mg2+ + SO42- — salt
D) KH2PO4 ⇌ K+ + H2PO4- — acid
E) H2SO4 ⇌ 2H+ + SO42- — acid

d. KH2PO4 <=> K+ + H2P04 - ———ACID

21) What is the type of bond between the hydrogen of one molecule and the nitrogen of another
molecule?

A) ionic bond
B) covalent bond
C) hydrogen bond
D) disulfide bond
E) hydrophobic bond

c. hydrogen bond

22) What is the type of bond between carbon, hydrogen, and oxygen atoms in organic molecules?
A) ionic bond
B) covalent bond
C) hydrogen bond

b. covalent bond

23) What is the type of bond between ions in salt?
A) ionic bond
B) covalent bond
C) hydrogen bond

a. ionic bond

24) A scientist wants to perform a test that will indicate whether a nucleic acid sample is composed of RNA or DNA. Testing
for the presence of which of the following is most appropriate in this situation?
A) phosphate
B) nitrogen
C) guanine
D) uracil
E) thymine

d. uracil

25) If you viewed one single protein using a microscope, you would observe multiple ________ structures.
A) primary
B) secondary
C) tertiary
D) primary and secondary
E) secondary and tertiary

b. secondary

26) Two antiparallel strands of DNA combine to form a double helix. The specific interactions that permit this phenomenon
occur by way of ________ bonds between ________.
A) hydrogen; deoxyriboses
B) hydrogen; nitrogenous bases
C) ionic; deoxyriboses
D) ionic; nitrogenous bases
E) ionic; phosphate groups

b. hydrogen; nitrogenous bases

27) Structurally, ATP is most like which type of molecule?
A) carbohydrate
B) lipid
C) protein
D) nucleic acid

d. nucleic acid

28) What do genes consist of?
A) carbohydrates
B) lipids
C) proteins
D) nucleic acids

d. nucleic acid

29) Which molecule is composed of a chain of amino acids?
A) carbohydrate
B) lipid
C) protein
D) nucleic acid

c. protein

30) Which are the primary molecules making up plasma membranes in cells?
A) carbohydrates
B) lipids
C) proteins

D) nucleic acid

b. lipids

31) The antimicrobial drug imidazole inhibits sterol synthesis. This would most likely interfere with
A) bacterial cell walls.
B) fungal cell walls.
C) eukaryotic plasma membranes.
D) prokaryotic plasma membranes.
E) genes

c. eukaryotic plasma membranes

36) Most amino acids found in cells demonstrate what type of chirality?
A) L-iosmers
B) D-isomers
C) C-isomers
D) B-isomers
E) A-isomers

a. L-isomers

38) An E. coli culture that has been growing at 37°C is moved to 25°C. Which of the following changes must be made in its
plasma membrane?
A) The number of phosphate groups must increase.
B) The viscosity must increase.
C) The number of saturated chains must increase.
D) The number of unsaturated chains must increase.
E) No changes are necessary

d. the number of unsaturated chains must increase

39) Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be
followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope 35S. After a 48-hour
incubation, the 35S would most likely be found in the S. cerevisiae's
A) carbohydrates.
B) nucleic acids.
C) water.
D) lipids.
E) proteins

e. proteins

40) Radioisotopes are frequently used to label molecules in a cell. The fate of atoms and molecules in a cell can then be
followed. Assume Saccharomyces cerevisiae is grown in a nutrient medium containing the radioisotope 32P. After a 48-hour
incubation, the majority of the 32P would be found in the S. cerevisiae's
A) plasma membrane.
B) cell wall.
C) water.
D) proteins.
E) carbohydrates

a. plasma membrane

41) Starch, dextran, glycogen, and cellulose are polymers of
A) amino acids.
B) glucose.
C) fatty acids.
D) nucleic acids.
E) acids.

b. glucose

42) Which of the following is a base?
A) C2H5OCOOH → H+ + C2H5OCOO-
B) C2H5OH
C) NaOH → Na+ + OH-
D) H2O → H+ + OH-
E) H2CO

c. NaOH → Na+ + OH-

43) Two glucose molecules are combined to make a maltose molecule. What is the chemical formula for maltose?
A) C3H6O3
B) C6H12O6
C) C12H24O12
D) C12H22O11

E) C12H23O10

D. C12H22O11

44) Desulfovibrio bacteria can perform the following reaction: S6- → S2-. These bacteria are
A) synthesizing sulfur.
B) reducing sulfur.
C) hydrolyzing sulfur.
D) oxidizing sulfur

D. oxidizing sulfur

45) If an amino acid contained a hydrocarbon as its side group, in which of the following categories could it be appropriately
designated?
A) hydrophilic
B) polar
C) nonpolar
D) basic
E) acidic

c. nonpolar

1) Which of the following is NOT equal to 1 mm?
A) 0.001 m
B) 10 6 nm
C) 0.1 cm
D) 100 μm
E) 10-3 m

D. 100 um

2) What structure does light pass through after leaving the condenser in a compound light microscope?
A) ocular lens
B) objective lens
C) specimen
D) illuminator

c. specimen

3) Which of the following pairs is mismatched?
A) nigrosin — negative stain
B) methylene blue — simple stain
C) acidic dye — capsule stain
D) basic dye — negative stain
E) crystal violet — simple stain

D. basic dye — negative stain

4) Which of the following places the steps of the Gram stain in the correct order?
1-Alcohol-acetone
2-Crystal violet
3-Safranin
4-Iodine
A) 1-2-3-4
B) 2-1-4-3
C) 2-4-1-3
D) 4-3-2-1
E) 1-3-2-4

C. 2-4-1-3

5) Which of the following pairs is mismatched?
A) alcohol-acetone — decolorizer
B) crystal violet — basic dye
C) safranin — acid dye
D) iodine — mordant
E) carbolfuchsin — basic dye

C. safranin — acid dye

6) Which of the following is NOT true regarding the acid-fast stain?
A) It is used to identify members of the genus Mycobacterium.
B) Acid-fast cells retain the primary dye after treatment with acid-alcohol.
C) If cells are acid-fast, they are gram-negative.

D) Acid-fast cells appear red in a completed acid-fast stain.
E) Non-acid-fast microbes appear blue in a completed acid-fast stain.

C. If cells are acid-fast, they are gram-negative

7) The purpose of a mordant in the Gram stain is to
A) remove the simple stain.
B) make the bacterial cells larger.
C) make the flagella visible.
D) prevent the crystal violet from leaving the cells.
E) make gram-negative cells visible.

D. prevent the crystal violet from leaving the cells

8) Which of the following places the steps in the correct sequence?
1-Staining
2-Making a smear
3-Fixing
A) 1-2-3
B) 3-2-1
C) 2-3-1
D) 1-3-2
E) The order is unimportant

C. 2-3-1

9) The negative stain is used to
A) visualize endospores.
B) determine Gram reaction.
C) determine flagella arrangement.
D) visualize capsules.
E) determine cell size.

D. visualize capsules

10) Simple staining is often necessary to improve contrast in which microscope?
A) compound light microscope
B) phase-contrast microscope
C) darkfield microscope
D) fluorescence microscope
E) electron microscope

A. compound light microscope

11) Which microscope is used to see internal structures of cells in a natural state?
A) compound light microscope
B) phase-contrast microscope
C) darkfield microscope
D) fluorescence microscope
E) electron microscope

B. phase-contrast microscope

12) Which microscope uses visible light?
A) confocal microscope
B) differential interference contrast microscope
C) fluorescence microscope
D) scanning acoustic microscope
E) scanning electron microscope

B. differential interference contrast microscope

3) Which microscope achieves the highest magnification and greatest resolution?
A) compound light microscope
B) phase-contrast microscope
C) darkfield microscope
D) fluorescence microscope
E) electron microscope

e. electron microscope

14) In using this microscope, the observer does NOT look directly at an image through a lens.
A) compound light microscope
B) phase-contrast microscope
C) darkfield microscope
D) fluorescence microscope
E) electron microscope

e. electron microscope

15) This microscope produces an image of a light cell against a dark background; internal structures are NOT visible.
A) compound light microscope
B) phase-contrast microscope
C) darkfield microscope
D) fluorescence microscope
E) electron microscope

c. darkfield microscope

16) A virus measures 100 nm in length. What is its length in μm?
A) 10 μm
B) 1 μm
C) .1 μm
D) 0.01 μm
E) 0.001 μm

c. .1 um

17) Which of the following is NOT useful for observing living cells?
A) phase-contrast microscope
B) darkfield microscope
C) scanning acoustic microscope
D) scanning electron microscope
E) brightfield microscope

D) scanning electron microscope

18) A microorganism measures 5 μm in length. Its length in mm would be
A) 500 mm.
B) 50 mm.
C) 0.5 mm.
D) 0.05 mm.
E) 0.005 mm

E) 0.005 mm

19) Which of the following correctly traces the path of light through the compound microscope?
A) light source; condenser; specimen; objective lens; ocular lens
B) condenser; light source; specimen; ocular lens; objective lens
C) light source; specimen; condenser; objective lens; ocular lens
D) condenser; light source; specimen; objective lens; ocular lens
E) light source; condenser; objective lens; specimen; ocular lens

A) light source; condenser; specimen; objective lens; ocular lens