Practice MCQs

Q1. The first virus discovered was:

a) Bacteriophage c) Tobacco mosaic virus
b) Influenza virus d) Smallpox virus
Q2. The crystallization of the Tobacco mosaic virus was achieved by:
a) Wendell Stanley c) Robert Koch
b) Max Theiler d) Paul Farmer
Q3. What is the basic structure of a virus?
a) Nucleus
b) Cell membrane
c) Genetic material surrounded by a protein coat
d) Mitochondria
Q4. Which of the following is not a characteristic of viruses?
a) They can reproduce c) They can infect living cells
independently d) They have genetic material
b) They lack cellular structure (DNA or RNA)
Q5. What is the purpose of the viral envelope?
a) Protection of the genetic material c) Assisting in viral replication
b) Facilitating viral entry into host d) Both a and b
cells
Q6. The process by which a virus enters a host cell is called:
a) Transduction c) Replication
b) Translation d) Adsorption
Q7. Cilia and flagella are absent in:
a) Animal cells c) Living cells
b) Bacterial cells d) Non-living cells
Q8. Which of the following disease causing agent is obligate parasite?
a) HIV c) Puccinia
b) HAV d) All of these
Q9. Which of the following is not a criterion for the classification of viruses?
a) Morphology b) Replication mechanism
c) Genetic material d) Host range
Q10. Which of the following is a characteristic feature of the influenza virus?
a) Enveloped virus c) Non-segmented genome
b) Double-stranded DNA d) Reverse transcriptase

Q11. Which virus is responsible for causing AIDS?

a) Influenza virus c) Hepatitis B virus
b) Human Immunodeficiency Virus d) Varicella-zoster virus
(HIV)
Q12. What type of genetic material is found in a retrovirus?
a) DNA c) Both DNA and RNA
b) RNA d) None of the above
Q13. The term "virion" refers to:
a) The infectious particle outside c) The host cell infected by the
the host cell virus
b) The viral genome d) The viral proteins
Q14. Polio viruses are:
a) Tadpole shaped c) Spherical viruses
b) Rod shaped viruses d) Spring like
Q15. The protein coat of a virus is known as:
a) Capsid c) Nucleocapsid
b) Envelope d) Membrane
Q16. What is the function of viral spikes in some viruses?
a) Attachment to host cells c) Protein synthesis
b) Replication d) DNA synthesis
Q17. Which of the following is true regarding retroviruses?
a) They contain RNA as their genetic material
b) They replicate using reverse transcriptase
c) They have a helical capsid d) They only infect bacteria
Q18. A virion is a:
a) Virus c) Envelope
b) Capsid d) None of these
Q19. The protein subunits that make up the capsid of a virus are called:
a) Enzymes c) Capsomeres
b) Monomers d) Spikes
Q20. Genome of virus is composed of:
a) DNA c) A and B
b) RNA d) Protein
Q21. Among followings, ______ enzyme is naturally found in human immunodeficiency
virus.
a) DNA polymerase c) RNA polymerase
b) Reverse transcriptase d) Ligase
Q22. The component responsible for determination of shape of virus?
a) Type of nucleic acid c) Type of hosts
b) Protein subunits d) Viral envelop
Q23. The complete mature and infection virus particle is known as:
a) Venom c) Genome
b) Virion d) Capsid
Q24. Which of the following is not related to enveloped virus?
a) They survive for a short time c) Their envelop is sensitive to sunlight
b) They are tolerant to antibodies d) Envelop is derived from host
Q25. The bacteriophage replicates only inside the:
a) Animal cell c) Fungal cell
b) Bacterial cell d) Both A & B
Q26. The term "bacteriophage" refers to viruses that infect:
a) Plants c) Bacteria
b) Animals d) Fungi
Q27. Which stage of the bacteriophage life cycle involves the integration of viral DNA
into the host bacterial genome?
a) Attachment c) Replication
b) Entry d) Lysogeny
Q28. Which enzyme is responsible for the replication of bacteriophage DNA within the
host cell?
a) RNA polymerase c) DNA polymerase
b) DNA ligase d) Reverse transcriptase
Q29. How do bacteriophages differ from animal viruses?
a) Bacteriophages have an envelope, while animal viruses do not.
b) Bacteriophages replicate inside the host nucleus, while animal viruses replicate in the
cytoplasm.
c) Bacteriophages infect bacteria, while animal viruses infect animal cells.
d) Bacteriophages use RNA as their genetic material, while animal viruses use DNA.
Q30. Which virus is responsible for causing the common cold?
a) Influenza virus c) Coronavirus
b) Rhinovirus d) Adenovirus
Q31. Measles is characterized by:
a) Skin rash and fever
b) Severe cough and respiratory distress
c) Joint pain and swelling
d) Yellowing of the skin and eyes
Q32. Poliovirus primarily affects the:
a) Respiratory system c) Digestive system
b) Nervous system d) Cardiovascular system
Q33. Mad cow disease is caused by
a) Virus c) Viroid
b) Virion d) Prion
Q34. Virus that affects genital organs
a) HCV c) HIV
b) HSV d) Pox virus
Q35. Which of the following is the simplest forms of pathogens causing disease
a) Viruses c) Fungus
b) Prions d) Amoeba
Q36. Oral herpes is caused by:
a) HIV-2 c) HSV-2
b) HCV d) HSV-1
Q37. __ is known to cause cancers in animals.
a) Polio virus c) HIV
b) HBV d) Rous sarcoma virus
Q38. Virus that attack on spinal cord is
a) Rabies c) Toga virus
b) HIV d) Poliovirus
Q39. Viral inflammation of parotid gland is commonly associated with
a) Mumps c) Herpes simplex
b) Smallpox d) Influenza
Q40. What does HIV stand for?
a) Human Influenza Virus c) Highly Infectious Virus
b) Human Immunodeficiency Virus d) Human Inherited Virus
Q41. How HIV is primarily transmitted?
a) Airborne droplets c) Contaminated food
b) Sexual contact d) Mosquito bites
Q42. Which organ does HIV primarily target in the later stages of infection?
a) Liver c) Kidneys
b) Lungs d) Brain
Q43. Which of the following body fluids can transmit HIV?
a) Sweat c) Blood
b) Saliva d) Tears
Q44. How can HIV be prevented from mother to child during childbirth?
a) Antiretroviral therapy (ART) c) Avoiding prenatal care
b) Exclusive breastfeeding d) C-section delivery
Q45. What is the final stage of HIV infection called?
a) Acute HIV infection
b) Asymptomatic HIV infection
c) AIDS (Acquired Immunodeficiency Syndrome)
d) HIV latency stage
Q46. What is the role of CD4 cells in the immune system?
a) Attack bacteria
b) Regulate the immune response
c) Produce antibodies
d) Destroy cancer cells
Q47. What is the window period for HIV testing?
a) 1 week
b) 1 month
c) 3 months
d) 6 months
Q48. The main target of HIV in AIDS is:
a) Liver cells c) Red blood cells
b) B lymphocytes d) Helper T lymphocytes
Q49. Which of the following is not true about human immunodeficiency virus?
a) It is a retrovirus
b) It is surrounded by any envelope
c) It does not cause AIDS
d) It causes deficiency of human immune system
Q50. Protein of HIV that helps in its fusion with T cells:
a) gp31 c) gp141
b) gp120 d) gp41