Defence Against Disease Practice Questions

Which chemical defence is found in tears?

Put a cross ( ☒ ) in the box next to your answer.

☐ A cilia

☐ B mucus

☐ C lysozyme

☐ D hydrochloric acid

Name the chemical defence made in the stomach that kills pathogens in swallowed food.

Describe how mucus and cilia protect the lungs from pathogens.

Smoking damages the cilia in the trachea.

Suggest why people who smoke get more lung infections.

Name the type of molecule on the surface of the bacteria that is recognised by the specific immune system.

Explain how the specific immune system destroys these bacteria.

Compare the antibody response after the second dose with the antibody response after the first dose.

Use data from the table in your answer.

Explain why the antibody concentration rises so quickly after the second dose.

A vaccine against whooping cough contains an inactive form of the bacterium that causes the disease.

Explain how this vaccine makes a child immune to whooping cough without making the child ill.

Calculate the percentage decrease in the number of cases reported between 2000 and 2015.

Explain, using the data in the table, why the number of cases of this disease fell between 2000 and 2015.

State what is meant by the term antigen.

Explain why a person who was vaccinated against last year's flu virus may not be protected against this year's flu virus.

A man eats food that contains harmful bacteria. Two days later he has a fever and feels very ill. After a week his immune system has destroyed the bacteria and he recovers.

A year later the same type of bacteria enter his body in food again, but this time he does not become ill.

Explain how the man's body defends itself against these bacteria on both occasions.