Lymphatic System

Question 1

What is the lymphatic system composed of?

Answer 1

• lymph
• lymphatic vessels
• lymphatic organs (red bone marrow, thymus, lymph nodes, tonsils, and spleen)

Question 2

What is lymph?

Answer 2

transparent, colorless (or slightly yellow), watery fluid that closely resembles blood plasma, but more dilute

Question 3

What do lymphatic capillaries collect? Why?

Answer 3

remnants of interstitial fluid along with cell debris and waste metabolic byproducts from different tissues (except nervous tissue) to form lymph

Question 4

What do lymphatic capillaries receive?

Answer 4

• lipid droplets from gastrointestinal tract

- lymphocytes from blood

Question 5

What are the 4 main functions of the lymphatic system?

Answer 5

1. drain excess interstitial fluid
   - lymphatic vessels pick up excess interstitial fluid from tissues and return it to the blood
2. transports dietary lipids
   - lymphatic vessels transport lipids and lipid-soluble vitamins from gastrointestinal tract to blood
3. filters lymph and blood
   - foreign substances carried by lymph are filtered by lymph nodes
   - old or defective blood cells are filtered by spleen
4. carries out immunological responses
   - some lymphatic organs (thymus) initiate responses against certain pathogens

Question 6

What do lymphatic vessels carry? Where does it go?

Answer 6

carry lymph and pass it through lymph nodes to be filtered

Question 7

Where are lymphatic vessels?

Answer 7

in all human organs, except CNS, eyeball, inner ear, and cartilages

Question 8

What do lymphatic vessels join together to form?

Answer 8

lymphatic trunks (larger lymphatic channels) that form lymphatic ducts

Question 9

What do lymphatic ducts drain into? Where?

Answer 9

venous system at junction of subclavian and internal jugular veins

Question 10

What are lymph nodes?

Answer 10

bean-shaped structures usually found in groups, accompanying deep and superficial blood vessels

Question 11

Where are lymph nodes particularly numerous?

Answer 11

axilla, neck, popliteal fossa, inguinal region, posterior abdominal wall, and mediastina

Question 12

What are lymph nodes the site of?

Answer 12

• lymph filtration

- B lymphocytes proliferation

Question 13

What is the thymus?

Answer 13

pinkish gland that weighs 10-15 g at birth, and reaches maximum of 30-40 g at puberty

Question 14

What is the thymus replaced by after puberty?

Answer 14

connective tissue

Question 15

What is the thymus gland formed by?

Answer 15

two lobes

Question 16

Where is the thymus gland?

Answer 16

anterior and superior mediastina

Question 17

What is the thymus the main site of?

Answer 17

T lymphocytes maturation

Question 18

What is the spleen?

Answer 18

oval shaped, largest of lymphatic organs

Question 19

Where is the spleen?

Answer 19

located in abdominal cavity in left hypochondriac region

Question 20

How many surfaces, borders, and poles of the spleen are there? What are they?

Answer 20

• 2 surfaces (medial and lateral)
• 2 borders (superior and inferior)
• 2 poles (anterior and posterior)

Question 21

What is the lateral or diaphragmatic surface of the spleen?

Answer 21

• smooth

- guarded by ribs IX-XI

Question 22

What is the medial or visceral surface of the spleen?

Answer 22

mainly related to stomach and left kidney

Question 23

What does the medial or visceral surface of the spleen carry?

What passes through this structure?

Answer 23

hilum

nerve fibers, splenic artery, splenic vein, and efferent lymphatic vessels pass through

Question 24

What are the 2 main functions of the spleen?

Answer 24

• filter old and damaged red blood cells from blood

- store platelets

Question 25

What are tonsils? Where are they located?

Answer 25

aggregates of more or less encapsulated lymphoid tissue situated at entrances to pharynx

Question 26

What is the function of the tonsils?

Answer 26

produce antibodies against antigens

Question 27

What are the 5 tonsils?

Answer 27

- pharyngeal tonsil - palatine tonsils (2) - lingual tonsils (2)

Question 28

Where is the pharyngeal tonsil?

Answer 28

roof of nasopharynx behind nasal cavity

Question 29

When does the pharyngeal tonsil reach its maximum size? What happens when it does?

Answer 29

before school age replaced by connective tissue then

Question 30

Where are the palatine tonsils?

Answer 30

lie at oropharynx (one on each side) between palatoglossal and palatopharyngeal arches

Question 31

Where are the lingual tonsils?

Answer 31

located at posterior ⅓ of tongue

Question 32

Describe the path of lymphatic drainage of the body.

Answer 32

lymph passes from lymphatic capillaries into lymphatic vessels, then through lymph nodes

Question 33

What happens when lymphatic vessels exit the lymph nodes in certain regions of the body?

Answer 33

form lymph trunks

Question 34

What are the main lymph trunks? (5)

Answer 34

``` lumbar intestinal bronchomediastinal subclavian jugular ```

Question 35

What do lymphatic trunks join to form? What do these structures do?

Answer 35

2 major channels: thoracic duct and right lymphatic duct both ducts drain into blood circulation

Question 36

Where does the thoracic duct start? Where does it pass next? Where does it drain into?

Answer 36

starts from cisterna chyli (lymphatic sac) located in front of vertebrae LI and LII passes through diaphragm, ascends in posterior mediastinum drains into junction of left internal jugular and left subclavian veins

Question 37

What is the cisternal chyli?

Answer 37

lymphatic sac

Question 38

What does the thoracic duct receive the lymph of?

Answer 38

- lower limbs - pelvic cavity - abdominal cavity - left side of thoracic cavity - left side of head and neck - left upper limb

Question 39

What is the right thoracic duct formed by?

Answer 39

union of right subclavian and right jugular trunks

Question 40

What does the right lymphatic duct empty into?

Answer 40

junction of right subclavian and right internal jugular veins

Question 41

What does the right lymphatic duct receive lymph of?

Answer 41

- right upper limb - right half of thorax - right side of head

Question 42

Lower Limb and Pelvis Lymphatic Drainage What is lymph of the lower limb collected by?

Answer 42

superficial and deep lymphatic vessels that accompany the corresponding veins

Question 43

Lower Limb and Pelvis Lymphatic Drainage What does the lymph of superficial and deep lymphatic vessels drain into?

Answer 43

inguinal lymph nodes, which in turn empty into pelvic lymph nodes

Question 44

Lower Limb and Pelvis Lymphatic Drainage What do pelvic lymph nodes also receive lymph of? What are they drained by?

Answer 44

pelvic viscera drained by lumbar trunks into cisterna chyli

Question 45

Lower Limb and Pelvis Lymphatic Drainage What do inguinal lymph nodes also receive lymph of?

Answer 45

- lower quadrant of anterior abdominal wall | - perineum

Question 46

Abdomen Lymphatic Drainage Where does the lymph of the alimentary canal, liver, pancreas, and spleen drain into?

Answer 46

pre-aortic lymph nodes, then into cisterna chyli via intestinal trunks

Question 47

Abdomen Lymphatic Drainage Where does the lymph of posterior abdominal wall, kidneys, glands, and adrenal glands drain into?

Answer 47

para-aortic lymph nodes, then into cisterna chyli through lumbar trunks

Question 48

Thorax Lymphatic Drainage Where does the lymph of thorax drain into?

Answer 48

parasternal, diaphragmatic, intercostal, and mediastinal lymph nodes lymph of these nodes empties into thoracic duct on left side, and right lymphatic duct on right side via bronchomediastinal trunks

Question 49

Head and Neck Lymphatic Drainage Where does the lymph of the head and neck drain into?

Answer 49

superficial and deep lymph nodes (associated with superficial and deep veins, respectively) these lymph nodes eventually drain into left thoracic duct on left side, and into right lymphatic duct on right side via jugular trunks

Question 50

Upper Limb Lymphatic Drainage Where does lymph of the upper limb drain into?

Answer 50

superficial and deep lymph nodes (associated with superficial and deep veins, respectively) these lymph nodes eventually drain into axillary lymph nodes, that drain into subclavian trunk, that empties into right lymphatic duct on right side and thoracic duct on left side

Question 51

Upper Limb Lymphatic Drainage What do axillary lymph nodes also receive?

Answer 51

- superficial lymph nodes of anterior thoracic wall | - upper quadrant of anterior abdominal wall