lymphatic system lecture MW% +

Question 1

What are the functions of the lymphatic system?

Answer 1

• Tissue fluid drainage
• Return of plasma and plasma proteins
• Absorbed fat transport from gut
• Immunity

Question 2

What is the composition of the lymphatic system?

Answer 2

•Lymph is fluid and plasma proteins only, but gains lymphocytes as it flows through Lymphatic capillaries and channels.

• Fats added in small intestine.

Question 3

Describe the flow of in lymphatic system?

Answer 3

• Flow is similar to that in veins, relying upon muscle contraction, pressure changes and gravity.
• Unidirectional because of valves.
• Fluid flow into extracellular spaces increases during infection due to protein accumulation (osmosis), this drives increased lymph flow and therefore immune response in nodes, as more antigens are presented and phagocytosis occurs.

Question 4

What are lymph nodes?

Answer 4

•Here, the immunological (acquired immunity) functions of lymph are located.

Question 5

Describe lymph node pathology?

Answer 5

• Primary tumours (lymphomas) such as Hodgkins
• Secondary tumours as a result of metastasis from other sites
• Infections such as tuberculosis and glandular fever (mononucleosis)
• Inflammatory hyperplasia.

Question 6

What are the constituents of lymph nodes?

Answer 6

• Afferent lymphatic vessels carry unfiltered lymph into the node. Here waste products, and some of the fluid, are filtered out.
• Efferent lymphatic vessels carry the filtered lymph out of the node so that it can continue its return to the circulatory system.

Question 7

Describe the drainage routes?

Answer 7

1. The right lymphatic duct clears the right arm and chest.
2. The thoracic duct clears all of the other areas of the body including both legs, the lower trunk, upper left of the chest, and the left arm.

These empty into the venous system at the Jugular/ Subclavian junction

Question 8

Where does the transported fat from the gut end up in?

Answer 8

• To the Superior Vena Cava (SVC?) and eventually to the liver for absorption.

Question 9

Describe the function of the spleen?

Answer 9

• Largest lymphatic organ
• Upper left quadrant of abdomen (peritonised)
• Contains large amount of blood, routinely discharged via smooth muscle action