Influenza Viruses a and B Contain Eight RNA Strands and Influenza

question 28

Multiple Choice

Influenza viruses A and B contain eight RNA strands and influenza virus C has seven strands. During antigenic drift, genes coding for glycoproteins recognized by the host immune system are mutated,
Whereas during antigenic shift, whole RNA strands can be swapped with those of another influenza
Virus, greatly increasing the virulence and transmissibility of the virus and minimizing the ability of
The host's defenses to recognize it. Which of the following statements is true?

• A) Genetic drift creates a need for an annual flu vaccine to keep up with the seasonal genetic changes, and if genetic shift occurs, an additional vaccine will have to be administered
• Since the shift creates a different strain of virus.
• B) Genetic drift creates a need for an annual flu vaccine to keep up with the seasonal genetic changes, and if a genetic shift occurs, the same vaccine will be effective against both
• Strains.
• C) If a novel strain resulting from antigenic shift appears, it is not necessary to get vaccinated because these strains are typically less pathogenic than seasonal strains.
• D) The worst influenza pandemics throughout history have occurred as a result of genetic drift rather than genetic shift.

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Definitions:

Center Link

A component in the steering system of a vehicle that connects the steering box to the wheel spindles.

Rack and Pinion

A type of linear actuator that converts rotational motion into linear motion using a circular gear (the pinion) engaging a linear gear (the rack).

Recirculating Ball

A type of steering system mechanism that utilizes a series of balls to reduce friction and provide smoother steering control.

Belt-driven

Describes mechanisms or devices powered by a belt, which transfers movement and power from one pulley to another.