Lymphatic system

Question 1

What is the lymphatic system composed off?

Answer 1

Composed of two parts- network of lymphatic vessels that connect to lymphoid organs

Question 2

What does the lymphatic system do?

Answer 2

Returns intersititual fluid that has escaped into the surrounding tissues from capillaries.

Question 3

What is lymph?

Answer 3

interstitual fluid along with soluble proteins, lipids, sugars and immune cells as well as any foreign substances make up a fluid called lymph

Question 4

What is meant by chyle?

Answer 4

lymphatic vessels of the gut are important in transporting digested lipids into the body, which mix with lymph to make a milky white solution.

Question 5

Explain the basic structure of the lymphatic system:

Answer 5

• lymph transported through lymphatic vessels through the use of one way valves in the vessels
• drain lymph from peripheral tissues towards collection of lymphoid tissues called lymph nodes
• lymph nodes are secondary lymphoid organs containing lymphocytes (T & B cells and dendritic cells) acting like filters for detecting and removing substances from the body
• the spleen also functions like a lymph node it directly filters blood for foreign substances
• after passing through lymph nodes the lymph drains into increasingly larger lymphatic trunks within the bodty (right and left duct(thoracic duct))- draisn back into major blood vessels within the body

Question 6

Explain how lymph nodes greatly reduce the amount of time taken for a lymphocyte with the matching receptor to find the right antigen:

Answer 6

• lymph nodes are scattered all throughout the body and are highly vascularised organs
• Naive T cells and B cells enter the lymph nodes from these blood vessels and come into contact with any foreign substances (antigens) transported from the tissues into the lymph
• This brings lymphocytes and antigens together and means that the time taken for lymphocyte with the right receptor to find the matching antigen is greatly reduced, accelerating immune response. Lymphocytes activated lymphocytes which either produce antigen or go on to circulate in the body.

Question 7

Name the primary lymphoid organs in the body:

Answer 7

• red bone marrow and the thymus gland

Question 8

Name the secondary lymphoid organs in the body:

Answer 8

• lymph nodes, spleen and tonsils