Microbiology worksheet with answers

What is a yeast?

1. AA multicellular parasite
2. BA type of spiral bacterium
3. CA single-celled fungus
4. DA small virus

Which of these is a protozoan?

1. ARotavirus
2. BCandida albicans
3. CEscherichia coli
4. DGiardia lamblia

In infection control, what is a vector?

1. AThe first person infected in an outbreak
2. BA drug used to prevent infection
3. CA living organism that carries a pathogen from one host to another
4. DAn object such as a door handle that carries germs between patients on a ward

What is the incubation period?

1. AThe time an antibiotic takes to work
2. BThe time a culture needs in the laboratory
3. CThe time between infection and the first symptoms
4. DThe time during which a patient remains infectious to others

Which statement is one of Koch's postulates?

1. AThe disease must respond to antibiotics
2. BThe organism must cause the same disease when introduced into a healthy susceptible host
3. CThe organism must be found in healthy people as well
4. DThe organism must be visible with the naked eye

Why are Gram-negative bacteria often harder to treat with antibiotics?

1. AThey divide much more slowly
2. BThey have no ribosomes
3. CTheir outer membrane blocks many drugs
4. DThey have a thicker peptidoglycan layer

Why is Chlamydia trachomatis usually diagnosed with nucleic acid amplification tests instead of routine culture on agar?

1. AIt is an obligate intracellular bacterium that cannot grow on ordinary media
2. BIt is a virus and has no DNA
3. CIt dies immediately in the presence of oxygen
4. DIt is too large to grow on agar plates

How do retroviruses such as HIV copy their genome into the host DNA?

1. AThe viral DNA is copied directly by host RNA polymerase
2. BThe viral RNA is translated into DNA by ribosomes
3. CReverse transcriptase makes DNA from viral RNA, and integrase inserts it
4. DHost DNA polymerase copies the RNA without help