$$\text{dNTP} \rightarrow \text{dNMP} + 2\text{PP}_i$$

Question 1

Which of the following best describes the central dogma of molecular biology?

Accepted Answer

DNA is transcribed into RNA, which is then translated into protein.

Question 2

During DNA replication, which enzyme is responsible for unwinding the double helix?

Accepted Answer

Helicase

Question 3

What is the primary difference between the leading and lagging strands during DNA replication?

Accepted Answer

The leading strand is synthesized continuously, while the lagging strand is synthesized discontinuously.

Question 4

Which of the following equations represents the energy released during nucleotide incorporation in DNA replication?

Accepted Answer

$$	ext{dNTP} ightarrow 	ext{dNMP} + 2	ext{PP}_i$$

Question 5

Which antibiotic targets bacterial gyrase to disrupt DNA replication?

Accepted Answer

Moxifloxacin

Question 6

In prokaryotic transcription, what is the function of the promoter region?

Accepted Answer

It is the site where RNA polymerase binds to initiate transcription.

Question 7

Which of the following is NOT a feature shared by bacterial and eukaryotic ribosomes?

Accepted Answer

Both have identical rRNA sequences.

Question 8

A mutation changes a DNA base from G to T, resulting in a stop codon in the mRNA. What type of mutation is this?

Accepted Answer

Nonsense mutation

Question 9

Which process allows bacteria to acquire antibiotic resistance genes from other bacteria of the same generation?

Accepted Answer

Horizontal gene transfer

Question 10

What is the role of small nuclear ribonucleoproteins (snRNPs) in eukaryotic cells?

Accepted Answer

They remove introns and splice exons together in mRNA processing.

Question 11

Which of the following best describes a plasmid?

Accepted Answer

A circular DNA molecule separate from the bacterial chromosome, often carrying non-essential genes.

Question 12

Which mechanism of genetic transfer involves a bacteriophage accidentally packaging bacterial DNA and transferring it to another cell?

Accepted Answer

Transduction

Question 13

What is the function of DNA ligase during DNA replication?

Accepted Answer

It joins Okazaki fragments on the lagging strand.

Question 14

Which codon is universally recognized as the start codon for translation?

Accepted Answer

AUG

Question 15

A frameshift mutation is most likely to result from:

Accepted Answer

An insertion or deletion of one or more nucleotide pairs.

Question 16

Which of the following statements about bacterial chromosomes is correct?

Accepted Answer

Bacteria usually have a single circular chromosome.

Question 17

Which of the following is a real-world example of horizontal gene transfer contributing to antibiotic resistance?

Accepted Answer

A bacterium acquiring resistance genes from a plasmid transferred via conjugation.

Question 18

Which of the following best explains why E. coli O157:H7 is pathogenic while other E. coli strains are not?

Accepted Answer

It has a different genotype due to acquisition of virulence genes.

Question 19

Which of the following drugs blocks the elongation of transcription in bacteria by binding to the β-subunit of RNA polymerase?

Accepted Answer

Rifampin

Question 20

Which of the following is a correct description of degeneracy in the genetic code?

Accepted Answer

Each amino acid is coded by several codons.

Microbial Genetics: From DNA to Protein Synthesis and Genetic Variation

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