Microbiology worksheet with answers

Free printable Microbiology worksheet: 8 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

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1.Easy

Why are viruses called obligate intracellular parasites?

  1. AThey can only replicate inside a living host cell
  2. BThey only live inside the intestine
  3. CThey always kill the host cell immediately
  4. DThey can only be seen inside a cell under a microscope
2.Easy

What is agar used for in a microbiology laboratory?

  1. ATo stain bacteria purple
  2. BTo kill bacteria on surfaces
  3. CTo make culture media solid
  4. DTo dissolve bacterial cell walls
3.Easy

Which is part of the body's first line of defence against infection?

  1. AIntact skin
  2. BCytotoxic T cells
  3. CMemory B cells
  4. DAntibodies
4.Medium

What is endotoxin?

  1. AA toxin produced only inside human cells
  2. BA protein toxin secreted by Gram-positive bacteria into the surrounding tissue
  3. CThe lipopolysaccharide in the outer membrane of Gram-negative bacteria
  4. DA toxin made by fungi in damp buildings
5.Medium

In the lysogenic cycle of a bacteriophage, what happens to the phage DNA?

  1. AIt is integrated into the bacterial chromosome as a prophage
  2. BIt is immediately used to make new phages that burst the cell
  3. CIt is destroyed by the bacterium
  4. DIt leaves the cell through the pilus
6.Medium

Which vaccine contains live attenuated (weakened) viruses?

  1. AHepatitis B vaccine
  2. BTetanus vaccine
  3. CMMR (measles, mumps, rubella)
  4. DInactivated influenza injection
7.Hard

After eating home-canned vegetables, a patient develops double vision, difficulty swallowing and a descending flaccid paralysis. What is the most likely cause?

  1. AA viral infection of the motor neurons
  2. BEndotoxin from Gram-negative bacteria
  3. CBotulinum toxin, which blocks acetylcholine release
  4. DTetanus toxin, which blocks inhibitory neurotransmitters
8.Hard

A healthcare worker's blood test is positive for anti-HBs (hepatitis B surface antibody) and negative for HBsAg and anti-HBc. What does this most likely mean?

  1. APast natural infection that has cleared
  2. BCurrent acute hepatitis B infection
  3. CImmunity from hepatitis B vaccination
  4. DChronic hepatitis B infection

Answer key

  1. 1. A · They can only replicate inside a living host cell
  2. 2. C · To make culture media solid
  3. 3. A · Intact skin
  4. 4. C · The lipopolysaccharide in the outer membrane of Gram-negative bacteria
  5. 5. A · It is integrated into the bacterial chromosome as a prophage
  6. 6. C · MMR (measles, mumps, rubella)
  7. 7. C · Botulinum toxin, which blocks acetylcholine release
  8. 8. C · Immunity from hepatitis B vaccination

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