Week 1 – The Lymphatic System

Question 1

What are the main functions of the lymph system?

Answer 1

1. Circulates body fluids - draining excess interstitial fluid
2. Defends body against disease through immune responses
3. Transports dietary lipids from the GI to blood (via specialised lymphatic capillaries - lacteals)

Question 2

What is the structure of lymphoid tissue and what do they contain?

Answer 2

Specialised form of reticular tissue that contains large numbers of lymphocytes

Question 3

What are the major lymphatic vessels?

Answer 3

Lymphatic capillaries
Lymphatic vessels
Lymph nodes
Lymphatic Trunks
Which drain into
Lymphatic Ducts
Thoracic duct (main duct)
and
Right lymphatic duct

Question 4

What are lymphatic capillaries?

Answer 4

One way structure allowing interstitial fluid in but not out
> permeability than blood capillaries, slightly larger, can absorb large molecules incl proteins and lipids

Question 5

What unite to form Lymphatic Trunks?

Answer 5

lymphatic vessels exit lymph nodes in a particular region of the body, they unite to form lymph trunks

Question 6

What are the 5 Lymphatic Trunks and what do they drain?

Answer 6

1. Lumbar - drains lower limbs
2. Intestinal
3. Bronchomediastinal - thoracic wall and heart
4. Subclavian - upper limbs
5. Jugular - head and neck

Question 7

What do the 2 lymphatic ducts do?

Answer 7

• Right lymphatic duct
  receives lymph from R jugular, R subclavian (upper limbs) and R bronchomediastinal (thoracic wall and heart) trunks
• Thoracic duct (main duct)
  receive lymph from L side of the head, Cx and chest, L upper limb, entire body inferior to the ribs

Question 8

What is lymph?

Answer 8

Any excess blood plasma which is not reabsorbed after being filtered through the blood capillary walls, drains into lymphatic vessels and become slymph (approx. 3ltrs)

Question 9

How does lymph move through the body?

Answer 9

transported by
milking action of skeletal muscles
pressure changes that occur during inhalation

Question 10

What are the 2 primary lymphoid organs?

Answer 10

1. RBM
2. Thymus

Question 11

What are the 3 secondary lymph organs (where most immune responses occur)?

Answer 11

1. lymph nodes
2. spleen (last resting place for RBC)
3. lymphatic nodules

Question 12

What is MALT?

Answer 12

• Mucosa-associated lymphatic tissue
• Lymphatic nodules scattered through the connective tissue of mucous membranes lining the GI, respiratory airways, urinary and reproductive tract

Question 13

What is the difference between diffuse and follicular lymphoid tissues?

Answer 13

• Diffuse lymphoid tissue: Found in loose connective tissue spaces, like those that line the GI tract and respiratory system.
• Follicular lymphoid tissue: large aggregations of MALT found in tonsils, Peyer’s patches and the appendix.

Question 14

What are:
1. Lymphedema
2. Buboes
3. Spleen Damage
4. and Lymphangitis

Answer 14

1. Lymphedema - blockage in lymph system causing pain and swelling
2. Buboes - swollen inflamed lymph node in armpit/ groin
3. Spleen Damage - ruptured spleen → internal bleeding
4. Lymphangitis - inflammation of lymphatic system