Microbiology worksheet with answers

What is meant by the normal flora (microbiota) of the body?

1. ABacteria that always cause mild infections
2. BThe white blood cells in healthy tissue
3. CMicroorganisms that normally live on or in the body without causing disease
4. DMicroorganisms found only in sick patients

What is the most effective single measure to prevent the spread of infection in hospitals?

1. AKeeping windows closed
2. BWearing a face mask at all times
3. CGiving every patient antibiotics
4. DHand hygiene

How is HIV mainly transmitted?

1. AThrough blood, sexual contact and from mother to child
2. BThrough mosquito bites
3. CThrough coughing, sneezing and sharing cups or cutlery with others
4. DThrough shared drinking glasses

Which bacterium is the most common cause of stomach ulcers?

1. AEscherichia coli
2. BClostridioides difficile
3. CHelicobacter pylori
4. DStaphylococcus aureus

How do people usually become infected with Legionella pneumophila?

1. ABy being bitten by an infected tick
2. BBy person-to-person spread through kissing
3. CBy eating undercooked chicken or unpasteurised milk products
4. DBy inhaling aerosols from contaminated water systems

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 are beta-lactamase inhibitors such as clavulanic acid combined with amoxicillin?

1. AThey kill bacteria by themselves through the cell membrane
2. BThey protect amoxicillin from bacterial enzymes that destroy it
3. CThey make amoxicillin active against viruses
4. DThey slow the excretion of amoxicillin by the kidneys, raising its level

Which feature distinguishes most exotoxins from endotoxin?

1. AExotoxins are proteins and can be turned into toxoid vaccines
2. BExotoxins are heat-stable lipids
3. CExotoxins are lipopolysaccharides of the Gram-negative outer membrane
4. DExotoxins are only released when bacteria die