Mastering Quiz: Chapter 7A Microbial Genetics

Why is DNA replication essential for a cell? a. An organism must copy its DNA to pass genetic information to its offspring. b. It allows the organism to repair any mistakes. c. All organisms require two copies of DNA. d. Because DNA is double-stranded.

a. An organism must copy its DNA to pass genetic information to its offspring.

Which statement about DNA replication is FALSE? a. DNA ligase adds nucleotides to the lagging strand. b. DNA polymerase builds a new strand by adding DNA nucleotides one at a time. c. The two strands of parental DNA are separated during DNA replication. d. The lagging strand is made of a series of pieces that must be joined together to make a continuous strand. e. Because the two strands of parental DNA run in opposite directions, the new strands must be made in different ways.

a. DNA ligase adds nucleotides to the lagging strand.

What is the function of the parental DNA in replication? a. It serves as the template for DNA replication. b. It allows for the DNA to be circular. c. It gives the cell two complete copies of the DNA. d. It is passed into the offspring of the parent.

a. It serves as the template for DNA replication.

During the initiation step of translation, the fMet charged tRNA assembles in which site of the ribosome? a. P site b. E site c. A site

a. P site

What is the initial target of RNA polymerase? a. The promoter b. The template DNA c. The terminator region

a. The promoter

What are the products of semiconservative replication for a double-stranded DNA molecule? a. Two double-stranded DNA molecules, each consisting of one parental strand and one daughter strand. b. Two double-stranded DNA molecules, one consisting of two parental strands and the other consisting of two daughter strands. c. One double-stranded DNA molecule, consisting of two daughter strands. d. One double-stranded DNA molecule consisting of one parental strand and one daughter strand.

a. Two double-stranded DNA molecules, each consisting of one parental strand and one daughter strand.

Which of the following does not occur during RNA processing? a. mRNA attaches to the small subunit of a ribosome. b. Adenine nucleotides are added to the end of the RNA strand, forming a tail. c. Segments of RNA that do code for the protein are reconnected. d. Segments of the RNA strand that do not actually code for the protein are removed. e. A modified guanine nucleotide is added to the beginning of the RNA strand as a cap.

a. mRNA attaches to the small subunit of a ribosome.

Ribosomes contain which of the following? a. rRNA b. mRNA c. tRNA d. mRNA, tRNA, and rRNA are all found as part of the ribosome.

a. rRNA

RNA that has hydrogen bonded to itself forms a a. stem loop. b. terminator sequence. c. termination protein. d. promoter sequence.

a. stem loop.

According to the animation, ribosomes move along the mRNA in which direction? a. 3' to 5' b. 5' to 3' c. Either 5' to 3' or 3' to 5'

b. 5' to 3'

What results from the process of translation? a. tRNA b. A polypeptide c. Ribosomes d. mRNA

b. A polypeptide

The molecule that seals the gaps between the pieces of DNA in the lagging strand is a. DNA polymerase. b. DNA ligase. c. RNA. d. the leading strand. e. the replication fork.

b. DNA ligase.

Which of the following build(s) new strands of DNA? a. The leading strand b. DNA polymerases c. The lagging strand d. The origins of replication e. Parental DNA

b. DNA polymerases

How would one increase the concentration of a particular polypeptide in a cell? a. Increase the amount of DNA b. Increase the level of transcription c. Increase the concentration of promoters

b. Increase the level of transcription

Which DNA strand is synthesized continuously? a. The leading and lagging strands are both synthesized continuously. b. Leading strand c. Neither the leading nor the lagging strand is synthesized continuously. d. Lagging strand

b. Leading strand

According to the animation, which of the following makes mRNA from the information stored in a DNA template? a. DNA polymerase b. RNA polymerase c. Ribosomes d. tRNA

b. RNA polymerase

How does the ribosome know if the entering charged tRNA is correct? a. The preceding amino acid will not permit it to enter the A site. b. The anticodon on the tRNA base pairs to the codon on the mRNA. c. The incorrect tRNA does not fit into the A site.

b. The anticodon on the tRNA base pairs to the codon on the mRNA.

What is the function of the connector proteins? a. They produce the Okazaki fragments. b. They link the leading strand DNA polymerase and the lagging strand DNA polymerase together. c. They allow DNA synthesis to occur in the 3' to 5' direction. d. They enable one parental DNA strand and one newly synthesized DNA strand to be held together.

b. They link the leading strand DNA polymerase and the lagging strand DNA polymerase together.

Which of the following is involved in bringing amino acids to the ribosomes? a. mRNA b. tRNA c. mRNA, tRNA, and rRNA are all involved in transporting amino acids to the ribosomes. d. rRNA

b. tRNA

RNA polymerase is guided by the a. RNA strand. b. template strand of DNA. c. coding strand of DNA.

b. template strand of DNA.

What would happen if the mRNA codon that coded for Cys was mutated in the third position from a U to an A? a. The codon would now code for Trp instead of Cys. b. The amino acid Cys would still be coded. c. A stop codon would be introduced prematurely.

c. A stop codon would be introduced prematurely.

How is bacterial translation different from eukaryotic translation? a. Bacterial translation does not involve ribosomes. b. mRNA is read 3' to 5'. c. Bacteria can begin translation before transcription has terminated.

c. Bacteria can begin translation before transcription has terminated.

Which one of the following does not play a role in translation? a. Ribosomes b. Anticodon c. DNA d. tRNA e. Amino acids

c. DNA

What characteristic of DNA allows two connected DNA polymerases to synthesize both the leading and lagging strands? a. DNA is double-stranded. b. DNA is antiparallel. c. DNA is flexible. d. DNA has a helical shape.

c. DNA is flexible.

During DNA replication, which nucleotide will bind to an A nucleotide in the parental DNA? a. U b. C c. T d. G e. A

c. T

Which of the following amino acids is coded by only one codon? a. His b. Tyr c. Trp d. Phe e. Glu

c. Trp

During elongation, how is the RNA synthesized? a. Left to right b. Right to left c. 3' to 5' d. 5' to 3'

d. 5' to 3'

Which of the following events occurs during transcription? a. The message in mRNA is translated into a protein. b. Those segments of the RNA strand that do not actually code for the protein are removed. c. mRNA binds to a ribosome in the cytoplasm. d. A molecule of RNA is formed based on the sequence of nucleotides in DNA. e. A cap is added to the RNA molecule.

d. A molecule of RNA is formed based on the sequence of nucleotides in DNA.

What kind of bond is formed when two amino acids join together? a. A polar bond b. An ionic bond c. A hydrogen bond d. A peptide bond

d. A peptide bond

Which of the following are terms associated with Okazaki fragments? a. Discontinuous b. DNA ligase c. Lagging strand d. Lagging strand, DNA ligase, and discontinuous

d. Lagging strand, DNA ligase, and discontinuous

How many codons code for the amino acid arginine? a. Four b. One c. Three d. Six

d. Six

Why is the DNA synthesis of the lagging strand considered discontinuous? a. DNA synthesis on the lagging strand occurs 3' to 5'. b. The lagging strand only produces single-stranded DNA molecules. c. The lagging strand only requires one primer instead of multiple primers. d. The synthesis is moving in the opposite direction from the replication fork.

d. The synthesis is moving in the opposite direction from the replication fork.

How is translation terminated? a. When there are no more charged tRNA molecules b. When the ribosome runs out of the mRNA c. When the A, P, and E sites are all filled d. When a protein called a release factor enters and binds to the A site

d. When a protein called a release factor enters and binds to the A site

Which of the following can be translated into protein? a. mRNA, tRNA, and rRNA are all translated into protein. b. rRNA c. tRNA d. mRNA

d. mRNA

The site of translation is a. the Golgi apparatus. b. ribosomes in the cell nucleus. c. the plasma membrane. d. ribosomes in the cell cytoplasm. e. the cell nucleus.

d. ribosomes in the cell cytoplasm.

Where would one find an uncharged tRNA molecule in a ribosome? a. In the A site b. In the A and P sites c. In the P site d. In the A, P, and E sites e. In the P and E sites f. In the E site

e. In the P and E sites

As shown in the animation, the start codon also codes for which amino acid? a. Serine b. Alanine c. Proline d. Glycine e. Methionine

e. Methionine

Which statement about DNA replication is CORRECT? a. The leading strand is one of the strands of parental DNA. b. The lagging strand is one of the strands of parental DNA. c. DNA ligase helps assemble the leading strand. d. The lagging strand is built continuously. e. The leading strand is built continuously, and the lagging strand is built in pieces.

e. The leading strand is built continuously, and the lagging strand is built in pieces.

GAU codes for a. proline. b. serine. c. isoleucine. d. tryptophan. e. aspartic acid.

e. aspartic acid.

Which of the following is a correct statement about mRNA? a. mRNA is transcribed from DNA in the cytoplasm. b. mRNA binds directly to amino acids during translation. c. mRNA includes a cap that consists of extra adenine nucleotides. d. Segments of mRNA that code for protein are removed before translation. e. mRNA moves from the nucleus to the cytoplasm following RNA processing.

e. mRNA moves from the nucleus to the cytoplasm following RNA processing.

Transcription produces which of the following? a. mRNA b. rRNA c. tRNA d. mRNA and tRNA e. mRNA and rRNA f. mRNA, tRNA, and rRNA are all produced by transcription.

f. mRNA, tRNA, and rRNA are all produced by transcription.