Immunity A2

Which of the following best describes the first line of defence of the human body against pathogens?

• To try and prevent entry of microorganisms

• To produce antibodies immediately

• To destroy all cells in the infected area

• To increase body temperature

Which of the following is an example of a non-specific defence mechanism?

• Phagocytosis

• Antibody production

• Memory cell formation

• Vaccination

What is a characteristic of the specific immune response?

• It is immediate and non-selective

• It is tailored to the specific pathogen

• It only involves skin and mucous membranes

• It does not involve lymphocytes

Explain why the specific immune response tends to provide long-term immunity, while the non-specific response does not.

• Because the specific response involves lymphocytes and memory cells, which remember the pathogen for future responses, while the non-specific response does not create memory.

• Because the non-specific response is faster and more effective.

• Because the specific response only targets bacteria.

• Because the non-specific response uses antibodies.

Which substance in the stomach acts as a sterilising agent by killing many bacteria that come in with food?

• Lysozyme

• Hydrochloric acid

• Mucus

• Bile

How does lysozyme help protect the body from infection?

• By clotting blood

• By hydrolysing bacterial cell walls and bursting bacteria

• By trapping micro-organisms in mucus

• By producing antibodies

COUGHING, SNEEZING, and VOMITING are examples of which type of mechanism in the body?

• Chemical barriers

• Passive expulsion mechanisms

• Active immune responses

• Hormonal responses

Explain how mucus and cilia work together to prevent infection in the respiratory tract.

• Mucus traps micro-organisms and cilia move them towards the glottis for expulsion

• Cilia produce mucus to destroy bacteria

• Mucus neutralizes acids and cilia absorb nutrients

• Cilia and mucus both produce antibodies

Which of the following best describes phagocytosis?

• The process by which large particles are taken up by cells via plasma-membrane derived vesicles.

• The process by which cells divide to form new tissues.

• The process by which oxygen is transported in the blood.

• The process by which nutrients are absorbed in the intestines.

During the inflammatory response, what causes the infected area to appear red?

• Increased blood flow to the area.

• Accumulation of pus.

• Loss of plasma from the blood.

• Presence of bacteria.