Question 1:
What is the meaning of immunity?
What is the meaning of immunity?
Answer:
Immunity is the body’s ability to fight against disease infections caused by pathogens or foreign substances, by specifically fighting the particular pathogen.
Question 2:
Name two characteristics of the skin that allows the skin to react as an effective first line of defence.
Name two characteristics of the skin that allows the skin to react as an effective first line of defence.
Answer:
The skin is a physical defence that prevents the entry of pathogens. The pH of the skin which ranges from 3 to 5 provides an acidic environment which is unfit for microbial growth.
Question 3:
How does the phagocyte destroy pathogens that have penetrated the first line of defence?
How does the phagocyte destroy pathogens that have penetrated the first line of defence?
Answer:
Phagocytes carry out phagocytosis by surrounding, trapping and digesting pathogens.
Question 4:
Differentiate between antigens and antibodies.
Differentiate between antigens and antibodies.
Answer:
Antigen is a foreign substance that enters the body.
Antigen is usually a protein molecule found on the wall or external membrane of a pathogen.
Antibody is a protein produced by lymphocytes that functions to destroy the antigen.