Lymphatic System

Question 1

Function of lymphatic system

Answer 1

• Tissue drainage
• Return plasma and plasma proteins
• absorbed fat transport from gut
• Immunity (antigens)

Drains into circulatory system at duct

Question 2

Explain tissue drainage/return of plasma proteins

Answer 2

drains escaped, cell-free plasma (tissue fluid) from the extracellular spaces back to the venous system (hence, problems with lymohatic system => swelling)

Question 3

Composition of Lymph

Answer 3

Fluid and plasma proteins: but gains lymphocytes as it flow through lymphatic capillaries and channels. Fats added in small intestine

Question 4

Why does fluid etc. enter the lymph

brief

Answer 4

easier for fluid to enter lymph than leave capillary

Question 5

Flow of lymph

Answer 5

similar to veins: relyes upon muscle contraction, pressure changes and gravity. Unidirectional because of valves

Question 6

How does an immune response in nodes arise

Answer 6

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 7

what type of lymphoid organ are lymph nodes

Answer 7

secondary

Question 8

Lymph nodes

Answer 8

• Lymphatic vessels periodically traverse lymph nodes (secondary lymphoid tissue). Here, the immunological (acquired immunity) functions of lymph are located
• Can be isolated or grouped (groups occur at basis of major arterial trunks)

Question 9

What do lymph nodes provide

Answer 9

Max surface/flow to allow antigen presentation to WBC to occur (aquired immunity)

Question 10

When are lymph nodes large

Answer 10

After infection (lots of antibodies)

Question 11

How do/can tumours spread

Answer 11

“shed” into extracellular space => lymph nodes => reproduce and main tumour grows => shed…

Question 12

germinal center

Answer 12

specialized microstructure that forms in secondary lymphoid tissues, producing long-lived antibody secreting plasma cells and memory B cells - found in center

Question 13

Why are there many lymph nodes in certain places (e.g. stomach or intestines/gut)

Answer 13

eat many antigens/foreign bodies and very cascular so lots of fluid must be returned (back to aorta)

Question 14

2 types of lymph node

(location)

Answer 14

• Deep
• Superficial (e.f. inguina nodesin and around the femoral triangle at the base of the lower limb (axillary)

Question 15

Primary tumour

Answer 15

Lymphoma (tumour of nodes)

Question 16

secondary tumours

Answer 16

As result of metastasis from other sites (cancer cells spread here)

Question 17

2 drainage routes

Answer 17

• Thoraciic duct (most occurs here)
• Right lymphatic duct

Question 18

What routes do deep lymphatic drainage follow

Answer 18

Routes of arterial supply

Question 19

What do the lymph ducts then do, and where

Answer 19

empty into the venous system at the jugular and subclavian junction

Question 20

Areas of body to drain into right lymphatic duct and thoracic duct

Answer 20

see sheet

Question 21

Lymph function: fat transport from gut

explain further

Answer 21

Lymph returning from the small intestine is laden with absorbed fats, which will also drain to the SVC and eventually to the liver for absorption.

Question 22

Explain the immune function of the lymphatic system a bit further

Answer 22

Lymphocytes generated and matured at lymphoid tissue:

• Thymus and Bone marrow (1) MHC 1 and MHC 11
• Spleen (2)
• Lymph nodes (2)
• Peyer’s Patches (2) - like lymph node but in wall of gut; small intestine
• Tonsils

Question 23

Where do we generally find lymphatic tissue

Answer 23

in places where infection is going to happen

Question 24

Explain the spleen

Answer 24

• Larges lymphatic organ
• upped left quadrant of abdomen (peritonised)
• contains large amount of blood, routinely discharges via smooth muscle action

Question 25

White pupl in spleen

Answer 25

Immune function where T and B lymphocytes are found

(similar to a lymph node)

Question 26

Where is there no lymph drainage

Answer 26

• epithelium
• cartilage
• bone
• CNS (maybe)
• majority of spleen/liver