Microbiology worksheet with answers

Why are viruses called obligate intracellular parasites?

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

Which of these is usually the smallest?

1. AA virus
2. BA bacterium
3. CA yeast cell
4. DA red blood cell

Edward Jenner is known for developing vaccination against which disease?

1. APolio
2. BRabies
3. CTuberculosis
4. DSmallpox

Which statement is one of Koch's postulates?

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

MRSA is resistant to methicillin because it has:

1. AAn efflux pump for every antibiotic
2. BAn altered penicillin-binding protein (PBP2a)
3. CA polysaccharide capsule that blocks the entry of all beta-lactams
4. DNo cell wall at all

Which bacterium causes whooping cough (pertussis)?

1. ACorynebacterium diphtheriae
2. BMycoplasma pneumoniae
3. CHaemophilus influenzae
4. DBordetella pertussis

Why must a negative-sense RNA virus such as influenza carry its own RNA-dependent RNA polymerase into the host cell?

1. AHost ribosomes cannot read any viral genes
2. BThe polymerase is needed to integrate the genome into host DNA
3. CHost cells cannot make mRNA from an RNA template
4. DThe polymerase protects the virus from antibodies

In the 1840s Ignaz Semmelweis lowered deaths from puerperal fever in a Vienna maternity clinic. What did he introduce?

1. AVaccination of all mothers before birth
2. BTreating mothers with penicillin
3. CHandwashing with chlorinated lime before examining women
4. DKeeping mothers in separate isolation rooms after delivery