Question

Immune System

1.Explain the difference between innate and adaptive mechanisms of immunity.

2.What are the three lines of defense in your body?

3.What is inflammation? What kind of immunity is it?

4.Identify the organs of the lymphatic system.

5.Describe the difference between an antigen and an antibody.

6.Explain the different reaction that will occur between two people’s immune systems upon exposure to a pathogen where one individual has been vaccinated for the pathogen and the other individual has never been exposed to the pathogen.

7.What are B-cells, phagocytes and macrophages?

8.Distinguish between Helper T-cells and Killer T-cells.

Answer 1

1. Innate immunity- it is activated by a wide variety of pathogens, confers broad protection. Its primary function is to controls the spread of infection and direct development of adaptive immunity.

Adaptive immunity- it is activated by a specific components of pathogens. Vaccines stimulate this type of immunity. Its primary function is clearance of infection and development of memory response.

2. ANSWER: 1st line of defence- barriers loke the skin, 2nd line of defence - non specific immune cells loke marcophages, dentritic cells 3rd line of defense- specific immune response by b and t lymphocytes.

3. ANSWER: Inflammation is a process by which the body's lymphocytes and marcophages protect us from invading bacteria and viruses. Inflammation is a type of nonspecific immunity.

4. ANSWER: Bone marrow, thymus, lymphoid organ, spleen, tonsil, lymph nodes.

5. ANSWER: Antigen- Substance that induce immune response in the body, it is mostly outside the body, it binds specifically to the epitope.

Antibody- proteins that recognise and binds to the antigen. It is prosuced from the body. It binds to the paratope.

8. ANSWER: Helper t cells carries CD4 cells used to induce immunity. It recognises antigen in association with MHC of class 2.

Killer t cells carries CD8 cells which are predominantly cytotoxic. It recognises antigen in association with MHC class 1.