Lymphatic system

Question 1

What structures make up the lymphatic system?

Answer 1

1. Lymph
2. Lymphatic Vessels
3. Tissues
4. Supporting Organs
   - Spleen
   - Thymus

Question 2

What is the function of the lymphatic system?

Answer 2

1. Manage Fluids
2. Fat Transport
   - Lacteals absorb fats
   directly to lymphatic
   system
3. Defense/ Protection
   - phagocytic cells
   - WBC
   - antibodies

Question 3

Lymphatic Vessel charcteristics

Answer 3

• One way
• Start as Blind Pouch
• Valves
• Highly (↑) Permeable
• Simple Squamous Endothelium

Question 4

How does the lymphatic vessel work? Explain

Answer 4

• The lymphatic vessels
  are made of simple squamous epithelium and look like shingles on a roof.
• One side of the endothelial cells are anchored by Collagen Fibers
• Endothelial cells work as a one way door only allowing things to enter the lymphatic vessel and not exit.
• When interstitial pressure increases the pressure pushed the “doors” or endothelial cells open forming gaps for fluid, cells, proteins and pathogens to enter
• As things flow into the lymphatic vessel, the lymphatics pressure increases and the interstitial spaces pressure decreases causing the gaps or doors to close.

Question 5

What flows into the lymphatic vessels?
Is it good or bad?

Answer 5

Good:
- Fluid
- Proteins
- Cells (WBC/ phagocytic but also cancer cells)
Bad:
- viruses
- bacteria
- cancer cells
(causes spread of cancer –> metastatic)

Question 6

What allows lymph to flow (movement of fluid) ?

Answer 6

Skeletal Muscle Pump
Respiratory Pump
Pulse of the Artery
Valves

Question 7

Organization of lymphatics

Answer 7

Lymph Capillaries
↓↓↓
Collecting Vessels
↓↓↓
Lymphatic Trunks
↓↓↓
Lymphatic Ducts
↓↓↓
Venous veins (Subclavian veins)

Question 8

What are the 9 lymphatic trunks and what do they drain?

Answer 8

Jugular Trunks (R / L)
- head, neck, face
Subclavian Trunks (R / L)
- upper extremities
Bronchomediastinal Trunks (R / L)
- thoracic organs
Lumbar Trunks (R / L)
- lower extremities
Intestinal Trunks (Singular)
- abdominal organs

Question 9

What are the lymphatic ducts and how much of the body do they drain?

Answer 9

Right Lymphatic Duct
( 1/3 ≈ 33 %)
Thoracic Duct
( 2/3 ≈ 67 %)

Question 10

What trunks drain into the Right Lymphatic Dact and where does that drain?

Answer 10

R Jugular Trunk
R Suclavian Trunk
R Bronchomediastinal Trunk
—-> Right Subclavian Vein

Question 11

What drains into the Thoracic duct

Answer 11

L Jugular Trunk
L Subclavian Trunk
L Bronchomediastinal Trunk

Cisterna Chyli
- R + L Lumbar Trunks
- Intestinal Trunk

—-> Left Subclavian Vein