BI 234|CMIS TEST PRACTICE EXAMS
QUESTIONS WITH ACCURATE AND
VERIFIED ANSWERS GUARANTEED PASS
Without using oxygen, some microorganisms can convert pyruvic acid to a variety of
end-products such as ethyl alcohol, lactic acid, acetic acid, and butyric acid. This
process is called:
a. Phosphorylation b. Fermentation c. Respiration d. Krebs cycle
e. None of the above is the name of this process
- Ans - B
Which of the following is NOT a true statement about the diagram at right?
a. Each enzyme is specific for its substrate
b. The diagram shows a metabolic pathway
c. The end-product serves as a competitive inhibitor of the substrate on Enzyme 1
d. The product of each enzyme reaction becomes a substrate for the next enzyme
e. None of the above (All are true statements)
- Ans - c
Starting with a single bacterial cell at time zero, assuming binary fission every 20
minutes, how many cells will be present in a culture after 3 hours?
a. 2.0 X 103 (2,000) b. 3.0 X 102 (300) c. 512 d. 1,024
e. None of the above (correct answer not given)
- Ans - C
Which of the following is NOT correctly matched?
a. Pasteurization: heating at 72o C for 15 seconds to kill pathogenic (diseasecausing)
microbes
b. Bacteriostasis: inhibiting, but not killing, bacteria
c. Disinfection: destruction of vegetative (non-endospore) pathogens on inanimate
objects
d. Sterilization: total destruction of all forms of microbial life, including endospores
e. None of the above (All are correctly matched)
- Ans - E
Which of the following is NOT true about mutations?
a. Nucleotide substitution in DNA can cause missense mutations
b. Nucleotide substitution in DNA can cause nonsense mutations
c. Mutations can be harmful but not beneficial to the cell
d. Mutagens increase the rate of mutation, but mutations are still random
e. Nucleotide insertion or deletion in DNA can cause frameshift mutations
- Ans - C
You perform a ten-fold serial dilution of a culture to determine the number of colony
forming units (CFU)
,per mL. You do a plate count with the growth results given below. The number of CFU
per mL in the original
culture was: a. 157,000 b. 1,000 c. 1,570,000 d. 157 e. Correct answer not given
(Illustration missing)
- Ans - A
In the bacterial growth curve shown at right, the vertical
axis shows logarithm of the number of bacteria and the
horizontal axis shows time in hours.
In which phase(s) does the rate of cell deaths
equal the rate of cell divisions?
a. A b. B c. C d. D e. B & D
(a=lag, B=log, C=stationary, D= death)
(illustration missing)
- Ans - C
The genotype of an organism is best defined as:
a. A type of base substitution mutation
b. Actual, expressed physical and biochemical properties of
an organism
c. A subunit of DNA composed of a nitrogenous
base, a pentose sugar, and a phosphate
d. A segment of DNA that codes for a functional product
e. An organism's genetic makeup; its collection of genes and entire
DNA
- Ans - E
In the figure at right, what is the Decimal Reduction Time for
the microbe being killed?
a. 24 minutes b. 4 minutes c. 12 minutes d. 1 minute
e. Cannot be determined from graph
(Illustration missing)
- Ans - B. Decimal reduction time is the time in minutes required to kill 90% of a
bacterial population at a given temp
Genetic information can be transferred horizontally from one
bacterial cell to another cell of the same generation (versus daughter cells), leading to
genetic recombination, by all of the following
EXCEPT:
a. Conjugation b. Transduction c. Transformation
d. Gene expression (transcription/translation/protein synthesis)
e. None of the above (All are mechanisms of "horizontal transfer" genetic
recombination)
- Ans - D
Which of the following is NOT true of transfer RNA (tRNA)?
, a. Any tRNA molecule can carry any amino acid (i.e, not specific for one amino acid)
b. Carries amino acids for addition to the growing protein chain
c. Interacts with mRNA during translation on the ribosome
d. tRNA contains the anticodons that pair with codons on mRNA
e. None of the above (all are true of tRNA)
- Ans - A
For the following DNA sequence (reading from left to right),
what will be the mRNA sequence after transcription?
DNA sequence: TACCATATAGGTATC
a. AUGCCCGUGGAAUAG
b. AUGCAUUUUGCGCGA
c. ATGGTATATCCATAG
d. AUGGUAUAUCCAUAG
e. Correct answer not given
- Ans - D. A*T C*G
For the mRNA sequence (question #29), what will be the amino
acid sequence following translation? (Use chart at right)
a. Met-His-Phe-Ala-Arg b. Met-Val-Tyr-Pro
c. Met-Pro-Val-Glu d. Pro-Val-Met-Leu-His
e. None of the above
- Ans - B
Bacterial conjugation can result in genetic recombination of the
recipient cell because:
a. It interferes with DNA replication during cell division
b. Donor cell DNA is accidentally inserted into viral
(bacteriophage) capsids
c. Donor (Hfr or F+) cells transfer chromosomal and/or plasmid
DNA to a recipient (F-) cell
d. DNA fragments from dead donor cells in the environment are
taken up by recipient cells
e. None of the above
- Ans - C. Conjugation is transfer of genetic material from one cell to another involving
cell-to-cell contact
A culture medium that suppresses the growth of unwanted microbes and encourages
desired microbes is called a:
a. Selective medium b. Chemically defined medium c. Reducing medium d. Complex
medium e. Differential medium
- Ans - A
Which of the following is NOT correctly matched?
a. Agar - complex polysaccharide from seaweed used as a solidifying agent in culture
media
QUESTIONS WITH ACCURATE AND
VERIFIED ANSWERS GUARANTEED PASS
Without using oxygen, some microorganisms can convert pyruvic acid to a variety of
end-products such as ethyl alcohol, lactic acid, acetic acid, and butyric acid. This
process is called:
a. Phosphorylation b. Fermentation c. Respiration d. Krebs cycle
e. None of the above is the name of this process
- Ans - B
Which of the following is NOT a true statement about the diagram at right?
a. Each enzyme is specific for its substrate
b. The diagram shows a metabolic pathway
c. The end-product serves as a competitive inhibitor of the substrate on Enzyme 1
d. The product of each enzyme reaction becomes a substrate for the next enzyme
e. None of the above (All are true statements)
- Ans - c
Starting with a single bacterial cell at time zero, assuming binary fission every 20
minutes, how many cells will be present in a culture after 3 hours?
a. 2.0 X 103 (2,000) b. 3.0 X 102 (300) c. 512 d. 1,024
e. None of the above (correct answer not given)
- Ans - C
Which of the following is NOT correctly matched?
a. Pasteurization: heating at 72o C for 15 seconds to kill pathogenic (diseasecausing)
microbes
b. Bacteriostasis: inhibiting, but not killing, bacteria
c. Disinfection: destruction of vegetative (non-endospore) pathogens on inanimate
objects
d. Sterilization: total destruction of all forms of microbial life, including endospores
e. None of the above (All are correctly matched)
- Ans - E
Which of the following is NOT true about mutations?
a. Nucleotide substitution in DNA can cause missense mutations
b. Nucleotide substitution in DNA can cause nonsense mutations
c. Mutations can be harmful but not beneficial to the cell
d. Mutagens increase the rate of mutation, but mutations are still random
e. Nucleotide insertion or deletion in DNA can cause frameshift mutations
- Ans - C
You perform a ten-fold serial dilution of a culture to determine the number of colony
forming units (CFU)
,per mL. You do a plate count with the growth results given below. The number of CFU
per mL in the original
culture was: a. 157,000 b. 1,000 c. 1,570,000 d. 157 e. Correct answer not given
(Illustration missing)
- Ans - A
In the bacterial growth curve shown at right, the vertical
axis shows logarithm of the number of bacteria and the
horizontal axis shows time in hours.
In which phase(s) does the rate of cell deaths
equal the rate of cell divisions?
a. A b. B c. C d. D e. B & D
(a=lag, B=log, C=stationary, D= death)
(illustration missing)
- Ans - C
The genotype of an organism is best defined as:
a. A type of base substitution mutation
b. Actual, expressed physical and biochemical properties of
an organism
c. A subunit of DNA composed of a nitrogenous
base, a pentose sugar, and a phosphate
d. A segment of DNA that codes for a functional product
e. An organism's genetic makeup; its collection of genes and entire
DNA
- Ans - E
In the figure at right, what is the Decimal Reduction Time for
the microbe being killed?
a. 24 minutes b. 4 minutes c. 12 minutes d. 1 minute
e. Cannot be determined from graph
(Illustration missing)
- Ans - B. Decimal reduction time is the time in minutes required to kill 90% of a
bacterial population at a given temp
Genetic information can be transferred horizontally from one
bacterial cell to another cell of the same generation (versus daughter cells), leading to
genetic recombination, by all of the following
EXCEPT:
a. Conjugation b. Transduction c. Transformation
d. Gene expression (transcription/translation/protein synthesis)
e. None of the above (All are mechanisms of "horizontal transfer" genetic
recombination)
- Ans - D
Which of the following is NOT true of transfer RNA (tRNA)?
, a. Any tRNA molecule can carry any amino acid (i.e, not specific for one amino acid)
b. Carries amino acids for addition to the growing protein chain
c. Interacts with mRNA during translation on the ribosome
d. tRNA contains the anticodons that pair with codons on mRNA
e. None of the above (all are true of tRNA)
- Ans - A
For the following DNA sequence (reading from left to right),
what will be the mRNA sequence after transcription?
DNA sequence: TACCATATAGGTATC
a. AUGCCCGUGGAAUAG
b. AUGCAUUUUGCGCGA
c. ATGGTATATCCATAG
d. AUGGUAUAUCCAUAG
e. Correct answer not given
- Ans - D. A*T C*G
For the mRNA sequence (question #29), what will be the amino
acid sequence following translation? (Use chart at right)
a. Met-His-Phe-Ala-Arg b. Met-Val-Tyr-Pro
c. Met-Pro-Val-Glu d. Pro-Val-Met-Leu-His
e. None of the above
- Ans - B
Bacterial conjugation can result in genetic recombination of the
recipient cell because:
a. It interferes with DNA replication during cell division
b. Donor cell DNA is accidentally inserted into viral
(bacteriophage) capsids
c. Donor (Hfr or F+) cells transfer chromosomal and/or plasmid
DNA to a recipient (F-) cell
d. DNA fragments from dead donor cells in the environment are
taken up by recipient cells
e. None of the above
- Ans - C. Conjugation is transfer of genetic material from one cell to another involving
cell-to-cell contact
A culture medium that suppresses the growth of unwanted microbes and encourages
desired microbes is called a:
a. Selective medium b. Chemically defined medium c. Reducing medium d. Complex
medium e. Differential medium
- Ans - A
Which of the following is NOT correctly matched?
a. Agar - complex polysaccharide from seaweed used as a solidifying agent in culture
media
