Q: Which equation correctly represents the process of viral attachment to a host cell?

$$\text{Virion} + \text{Host Cell} \rightarrow \text{Virion-Host Cell Complex}$$

Question 1

Which process of horizontal gene transfer in bacteria requires direct cell-to-cell contact and involves the transfer of plasmid DNA through a pilus?

Accepted Answer

Conjugation

Question 2

A bacterium acquires resistance to an antibiotic by taking up naked DNA fragments from its environment. Which process is responsible for this gene transfer?

Accepted Answer

Transformation

Question 3

During generalized transduction, what is the source of DNA that is mistakenly packaged into a phage particle?

Accepted Answer

Random fragments of bacterial chromosomal DNA

Question 4

Which of the following statements best describes a prion?

Accepted Answer

A proteinaceous infectious agent lacking nucleic acid

Question 5

A patient is diagnosed with Creutzfeldt–Jakob Disease (CJD). What is the most likely cause of this disease?

Accepted Answer

Spontaneous misfolding of PrP protein or exposure to contaminated tissue

Question 6

Which of the following is TRUE about specialized transduction?

Accepted Answer

It occurs during the lysogenic cycle and transfers specific bacterial genes near the phage insertion site.

Question 7

Which of the following viruses is associated with the development of human cancers such as Burkitt’s lymphoma and Hodgkin’s lymphoma?

Accepted Answer

Epstein-Barr virus (EBV)

Question 8

Which of the following best describes the structure of a viroid?

Accepted Answer

A circular piece of single-stranded RNA lacking a protein coat

Question 9

Which equation correctly represents the process of viral attachment to a host cell?

Accepted Answer

$$	ext{Virion} + 	ext{Host Cell} ightarrow 	ext{Virion-Host Cell Complex}$$

Question 10

Which of the following is a key difference between the lytic and lysogenic cycles of bacteriophages?

Accepted Answer

The lysogenic cycle allows the phage genome to remain dormant within the host chromosome.

Question 11

Which of the following is a consequence of horizontal gene transfer in bacteria?

Accepted Answer

Acquisition of antibiotic resistance genes

Question 12

A virus with a lipid envelope and surface proteins derived from the host cell is classified as:

Accepted Answer

Envelope virus

Question 13

Which of the following best explains why prion diseases are extremely resistant to heat, radiation, and disinfectants?

Accepted Answer

Prions lack nucleic acids and are composed solely of misfolded proteins.

Question 14

Which step in the animal virus replication cycle involves the synthesis of new viral proteins and nucleic acids using the host cell’s machinery?

Accepted Answer

Synthesis

Question 15

Which of the following is a correct description of latency in viral infections?

Accepted Answer

The viral genome remains inactive within the host cell for extended periods.

Question 16

Which of the following is TRUE about retroviruses?

Accepted Answer

They use reverse transcriptase to convert their RNA genome into DNA.

Question 17

Which of the following equations represents the process of generalized transduction?

Accepted Answer

$$	ext{Phage} + 	ext{Bacterial DNA} ightarrow 	ext{Phage-Bacterial DNA Complex}$$

Question 18

Which of the following is a major symptom of Bovine Spongiform Encephalopathy (BSE) in cattle?

Accepted Answer

Behavior changes and loss of coordination

Question 19

Which of the following is a plausible outcome of lysogenic conversion in bacteria?

Accepted Answer

Acquisition of toxin genes leading to increased pathogenicity

Question 20

Which of the following best describes the role of the envelope in enveloped viruses?

Accepted Answer

It helps the virus evade the host immune system and facilitates entry into host cells.

Horizontal Gene Transfer, Viruses, and Prions: Key Concepts in Microbial Genetics and Infectious Disease

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