All Free Microbiology MCQs with Answers

• A. T. Solium
• B. Echinococcus granulosus
• C. T. Saginata
• D. nana

Explanation: Cysticercosis cellulosae is the larval tissue infection caused by Taenia solium, especially when humans ingest its eggs.

• A. Bilurubin
• B. Haemoglobin
• C. Iron
• D. Haematin-globin pigment

Explanation: Malaria pigment, or haemozoin, is a brown-black haematin-containing pigment formed when Plasmodium digests haemoglobin inside red cells.

• A. Sporozoite
• B. Merozoite
• C. Hypnozoite
• D. Gametocyte

Explanation: The bite of an infected Anopheles mosquito injects Plasmodium sporozoites into the human bloodstream, and these first invade liver cells.

• A. Cysts in the sterile pus
• B. Trophozoites in the pus
• C. Cysts in the intestine
• D. Trophozoites in the feces

Explanation: Amoebic liver abscess is supported by finding Entamoeba histolytica trophozoites in the abscess material, particularly near the abscess…

• A. Lymphocytes
• B. Neutrophilis
• C. Eosinophils
• D. Basophils

Explanation: Helminthic and many other parasitic infections commonly stimulate eosinophilia, so eosinophils predominate in the typical parasitic…

• A. Dog tapeworm
• B. Hookworm
• C. Fish tapeworm
• D. Threadworm

Explanation: The fish tapeworm, classically Diphyllobothrium latum, can cause vitamin B12 deficiency by competing for intestinal B12 and thereby…

• A. Kalahazar
• B. Toxoplasmosis
• C. Malaria
• D. Sleeping sickness

Explanation: LD bodies, or Leishman-Donovan bodies, are intracellular amastigotes of Leishmania donovani found in macrophages in kala-azar, or visceral…

• A. Parasitic in nature
• B. Fungal
• C. Congenital
• D. Viral

Explanation: A hydatid cyst is a parasitic cyst produced by the larval stage of Echinococcus granulosus, usually involving the liver or lungs.

• A. Left lobe of liver is commonly involved
• B. Portal system is the main filtration system
• C. Trophozoites can be visualized in the pus
• D. Non-suppurative form is the serious form of extra intestinal amoebiasis

Explanation: Entamoeba histolytica trophozoites may be found in the pus or, more reliably, at the margin of an amoebic liver abscess.

• A. Acute infection
• B. Carrier state
• C. Prodromal phase
• D. Convalescence

Explanation: A rise in anti-HBc, particularly the IgM component, indicates a recent or acute hepatitis B infection.

• A. Virus
• B. Bacteria
• C. Spirochete
• D. Anaerobe

Explanation: Cytopathic effects are visible structural and functional changes produced in virus-infected host cells, such as cell rounding, lysis, or…

• A. New virus particle arises directly (by division) from preexisting viruses
• B. Fall in to the general size range of 200-3000 angstrom unit
• C. Contain equal proportions of protein, lipo polysaccharide and nucleic acids
• D. Contain DNA but no RNA

Explanation: Viruses commonly measure about 20 to 300 nm, equivalent to roughly 200 to 3000 angstroms.

• A. Chick embryo
• B. Blood agar
• C. Guinea pigs
• D. Cell culture

Explanation: Viruses require living cells for replication, so they can be grown in embryonated eggs, laboratory animals, or cell cultures.

• A. The time lapse between the infection and detection of viral antibodies
• B. The time lapse between the infection and development of AIDS
• C. The time lapse between obtaining the sample and detection of virus in the lab
• D. None of the above

Explanation: The HIV window period is the interval after infection during which antibodies have not yet reached detectable levels.

• A. Red blood cells
• B. Fibroblasts
• C. Helper T lymphocytes (CD4)
• D. Mast cells

Explanation: HIV preferentially infects CD4 helper T lymphocytes through the CD4 receptor and chemokine co-receptors, progressively weakening…

• A. Apthous stomatitis
• B. Tuberculosis
• C. Pneumocystis carinii pneumonia
• D. Herpetic gingivostomatitis

Explanation: Pneumocystis jirovecii pneumonia, formerly called Pneumocystis carinii pneumonia, is the classic AIDS-defining opportunistic infection.

• A. Rheo
• B. Retro
• C. Rhabdo
• D. Flavi

Explanation: HIV is a retrovirus because it carries reverse transcriptase and converts its RNA genome into DNA during replication.

• A. Pox virus
• B. Measles virus
• C. Hepatitis B virus
• D. HIVConsult Online Doctors

Explanation: Measles virus produces both intranuclear and intracytoplasmic inclusion bodies, including cytoplasmic Warthin-Finkeldey-type cells.

• A. Rabies
• B. Poliomyelitis
• C. Influenza
• D. Herpes

Explanation: Rabies vaccination is given after exposure has begun because post-exposure prophylaxis can prevent the virus from reaching the central…

• A. Composed largely proteins without any nucleic acid
• B. Phase in which virus cannot be demonstrated in host cell
• C. Viruses which are genetically deficient
• D. Viral components may be synthesized but maturation & assembling is defective

Explanation: Prions are infectious protein particles composed largely of abnormal protein and contain no DNA or RNA.