lymphatics

Question 1

what does the lymphatic system consist of?

Answer 1

lymph (fluid), lymphatic vessels, lymphoid organs (e.g. thymus - T cell maturation)

Question 2

describe the structure of lymphatic system

Answer 2

a circulatory system with valves

Question 3

where are the lymph nodes located?

Answer 3

along lymphatic vessels

Question 4

describe the organisation of the lymphatic system

Answer 4

• organ plexuses drain into lymphatic vessels, then passes through lymph nodes
• most lymph drains via thoracic duct
• lymph drains back into venous system at left venous angle

Question 5

what are the 3 functions of the lymphatic system?

Answer 5

1. drainage of interstitial fluid from the extracellular space
2. transport of dietary lipids in lacteals
3. immune response: defense mechanism against foreign proteins

Question 6

describe the process of transporting dietary lipids

Answer 6

• lipids are absorbed into lacteals in the small intestine
• lipids are then transported in the lymph (a.k.a. chyle) as chylomicrons
• lipids are then transported to the liver via the blood circulation

Question 7

label this diagram with the lymphatic capillaries, blood capillaries, interstitium and afferent lymphatic vessel

Question 8

what are the 2 main ways the lymphatic system functions to help immune response?

Answer 8

1. act as a phagocytic filter - prevent unwanted partiles (e.g. microbes) from entering blood circulation
2. provide a site for lymphocytes to come into contact with antigens, which increases the immune response through lymphocyte proliferation

Question 9

how is lymphatic flow maintained?

Answer 9

hydrostatic pressure between interstitial fluid and lymph

• regulates expansion and compression phases

Question 10

how is lymphatic flow in lacteals assisted?

Answer 10

peristalsis of the gut