Microbiology worksheet with answers

Vaccines protect against disease mainly by:

1. AProviding ready-made antibodies that remain in the blood for life
2. BKilling bacteria directly in the blood
3. CBlocking all viruses from entering cells
4. DStimulating the immune system to form memory cells

What is the purpose of pasteurising milk?

1. ATo add healthy bacteria to the milk
2. BTo remove fat from the milk
3. CTo kill pathogens by heating, without fully sterilising it
4. DTo kill all microorganisms, including bacterial spores, by heating

What is a zoonosis?

1. AAn infection spread through water
2. BAn infection that spreads from animals to humans
3. CAn infection caught in hospital
4. DAn infection that only affects zoo animals

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

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

Transfer of bacterial genes from one bacterium to another by a virus is called:

1. ATransformation
2. BTranscription
3. CTransduction
4. DConjugation

How is DNA transferred between bacteria during conjugation?

1. ABy a bacteriophage carrying bacterial DNA
2. BBy fusion of two bacterial cells into one
3. CBy uptake of free DNA from the environment
4. DThrough direct contact using a sex pilus

Gram-positive cocci are found. Which test quickly separates staphylococci from streptococci?

1. AGrowth on MacConkey agar
2. BThe coagulase test
3. CThe catalase test
4. DThe acid-fast stain

Which hepatitis viruses are mainly spread through contaminated food and water?

1. AHepatitis C and E
2. BHepatitis A and E
3. CHepatitis B and C
4. DHepatitis B and D