Viruses Knowledge-Based Download PDF

Questions

1. 1.

   In enveloped viruses, which structures act as spikes that recognize and bind to specific receptor molecules on the host cell membrane?

   • A) Capsomeres forming the internal capsid
   • B) Glycoproteins embedded in the viral envelope
   • C) Matrix proteins lining the envelope interior
   • D) Host-derived phospholipids of the lipid bilayer
2. 2.

   During the replication and release of enveloped animal viruses, which source primarily provides the lipid bilayer of the viral envelope?

   • A) De novo synthesis carried out by viral enzymes in the host cytoplasm
   • B) Enzymatic breakdown and reassembly of the host cell wall
   • C) Host cell membrane systems, such as the plasma membrane or endoplasmic reticulum
   • D) Structural capsomers that spontaneously transform into a phospholipid matrix
3. 3.

   Which enzyme enables retroviruses to synthesize a complementary DNA strand using their viral RNA genome as a template?

   • A) DNA helicase
   • B) RNA replicase
   • C) Reverse transcriptase
   • D) DNA topoisomerase
4. 4.

   During the lysogenic cycle of a temperate bacteriophage, which of the following events happens to the viral genome after entering the host bacterium?

   • A) It immediately directs the production of new viral proteins and hydrolyzes the host chromosome.
   • B) It integrates into the host bacterial chromosome and remains latent as a prophage.
   • C) It utilizes host ribosomes to undergo independent binary fission within the cytoplasm.
   • D) It forms a lipid envelope around itself while actively assembling mature virions.
5. 5.

   Which of the following characteristics is true for all viruses and distinguishes them from cellular organisms?

   • A) They possess a functional cell membrane equipped with active transport proteins.
   • B) They lack ribosomes and cannot independently generate ATP or synthesize proteins.
   • C) They possess both double-stranded DNA genomes and ribosomes within each mature particle.
   • D) They are capable of autonomous reproduction through binary fission in extracellular broth.