Wray- Lymphatic System

Question 1

Lymphatic function: (2)

Answer 1

1. Transport excess fluid from tissue –> blood stream

2. Immune response

Question 2

Lympatic flaps (minivalve) open due to an increase in __________

Answer 2

Blood Pressure

Question 3

Flaps: (2 function)

Answer 3

1. Anchored to connective tissue prevent the lymph vessel from collapsing
2. Opens/closes depending on pressure from tissue

Question 4

Two major ducts:

Answer 4

1. Right lymphatic duct: empties from head, neck and upper limbs (SMALL)
2. Thoracic duct: empties from everything else (lower limbs, abdominal region, left upper limbs, thorax, left side of head and neck) (LARGE)

Question 5

Flow:

Answer 5

• No pump/no pressure

- Bundled with arteries surrounded by connective tissue which helps lymph flow

Question 6

Cells of lymph

Answer 6

1. Macrophage
2. Lymphatic cells (B and T cells)
3. Dendritic cells: capture marked foreign particle and bring it to the nodes. (phagocytic)

Question 7

Lymph Node

Answer 7

1. Filter Lymph
2. Monitor body fluid for pathogens
3. Bottleneck effect (exit) allows fluid to remain in node for longer period of time, which allows more time to filter.

Question 8

Thymus: structure and location

Answer 8

1. Bi-lobed

2. Anterior to aorta; posterior to sternum

Question 9

Thymus: function

Answer 9

1. Maturation of T-lymphocytes
2. Undergoes changes:
   
   • infancy/childhood: highly active
   • adulthood: 40% active
   • older age (70s): 80%
   • Replaced with fat when degrades

Question 10

Spleen: Location

Answer 10

Lateral to the stomach

Question 11

Spleen:

Answer 11

1. Largest lymphatic organ

2. Red (destroys RBCs) and white pulp (destroys WBCs)

Question 12

Tonsils: 3 locations

Answer 12

1. Pharyngeal tonsil
2. Palatine tonsil
3. Lingual tonsil

Question 13

Tonsils: function

Answer 13

Collect pathogens that enter the mouth and nasal cavity through food or breathing

Question 14

Peyer’s patches: location

Answer 14

On the walls of distal portion of small intestine