Lymphatic System

Question 1

Why do we need it?

Answer 1

bring back and restore lymph that leaks from the capillary beds that are very thin

Question 2

What is lymph?

Answer 2

• all of blood plasma material that leaks out of capillary beds
• fluid connective tissue
• recovered interstitial fluid
• lymphocytes (T,B cells)
• macrophages

Question 3

Functions of the lymphatic system:

Answer 3

1. return interstitial fluid to veins
2. distribute lymphocytes made in red marrow, spleen, and thymus
3. transport lipids absorbed by small intestine using “lacteals”
4. take in bacteria, viruses, or cancer cells

Question 4

Components of lymphatic system:

Answer 4

1. lymphatic vessels
2. lymphoid nodules
3. lymphoid organs

Question 5

Lymphatic vessels

Answer 5

• vessels have beaded appearance (from one-way valves; low pressure in vessel)
• locomotion powers lymph

Question 6

What are the 2 lymphatic ducts that drain into veins and which veins?

Answer 6

1. right lymphatic duct - into right subclavian vein (1/4)
2. thoracic duct - into left subclavian (3/4)

Question 7

Lymphoid nodules

Answer 7

swelling/node where there are many lymphocytes in reticular fiber framework

Question 8

What is the MALT?

Answer 8

mucosa-associated lymphoid tissue (makes sure everything is “safe” - they detect antigens entering body)

Question 9

Where are lymphoid nodules located?

Answer 9

1. digestive
2. respiratory
3. urinary
4. reproductive tracts
   (everything in contact with outside world)

Question 10

What are two types of MALTs?

Answer 10

1. Tonsils
2. Peyer’s patches

Question 11

What do tonsils do and where are they located?

Answer 11

remove pathogens in pharynx (pharyngeal, palantine, lingual)

Question 12

What are Peyer’s patches and where are they located?

Answer 12

detect foreigners in feces - aggregate lymphoid nodules in the ileum

Question 13

What are the lymphoid organs?

Answer 13

1. lymph nodes
2. thymus
3. spleen

Question 14

What are the locations of the lymph nodes?

Answer 14

1. cervical lymph nodes
2. axillary
3. lumbar

Question 15

What are lymph nodes?

Answer 15

“check station” - check identity before allowing into the circulatory system - filter returning fluid

Question 16

What are the functions of lymph nodes?

Answer 16

filter antigens from lymph

Question 17

Why do my lymph nodes hurt when I’m sick?

Answer 17

nodes swell with lymphocytes & macrophages fighting infection

Question 18

How are lymph nodes used to detect metastatic cancer?

Answer 18

cancer cells enter lymphatic capillaries - lymph nodes are way-stations of metasiss

Question 19

Why does cancer spread?

Answer 19

1. cancers are not cohesive tissue
2. cancer cells get stuck in narrow ducts in lymph nodes

Question 20

TNM staging

Answer 20

t= tumor (how big)
n= node (in nodes or not in nodes)
m= metastasis (how far it spread)

Question 21

Answer 21

a- arteriole
b- lymphatic capillary
c- capillary bed
d- venule

Question 22

Answer 22

a- interstitial fluid
b- opening
c- lymph

Question 23

Answer 23

a- capillary
b- lacteal
c- lymph vessel

Question 24

Answer 24

anatomy of lymph nodes
a- lymph nodules
b- lympocytes
c- efferent lymph vessel
d- cortex
e- afferent lymph vessel