Lymphatics

Question 1

What is lymph made up of

Answer 1

Fluid and plasma proteins only
It can gain lymphocytes as it flows through the lymphatic capillaries and channels (e.g. fats will be added in the small intestine)

Question 2

What does the flow in the lymphatic system rely upon

Answer 2

Muscle contraction
Pressure changes
Gravity

Question 3

What is the flow in the lymphatic system similar to

Answer 3

Veins

Question 4

Why is the flow in the lymphatic system unidirectional

Answer 4

Due to valves

Question 5

What happens to the fluid flow into extracellular spaces an infection

Answer 5

Increases due to protein accumulation (osmosis) which drives an increased lymph flow and therefore the immune response in the nodes, as more antigens are being presented and phagocytosis occurs

Question 6

What are the 4 main functions of the lymphatic system

Answer 6

Tissue drainage
Return of plasma and plasma proteins
Absorb fat from the gut
Immunity

Question 7

How can the lymphatic system drain tissue and return plasma proteins

Answer 7

Drains must escape cell-free plasma (tissue fluid) from the extracellular spaces back to the venous system (about 8L a day)

Question 8

What does a lymph node consist of

Answer 8

Mass of lymphatic tissue that is surrounded by a fibrous capsule

Every node is connected to an incoming and outgoing lymph vessel

Question 9

What are germinal centres

Answer 9

Secondary lymphoid follicles

Question 10

What are lymph nodes

Answer 10

Secondary lymphoid tissues of about 0.1-2.5cm in diameter where the immunological (acquired immunity) functions of the lymph are located

Question 11

Lymph nodes can be

Answer 11

Isolated

Grouped

Question 12

Where are grouped lymph nodes found

Answer 12

At the bases of major arterial trunks

Question 13

How much lymph is approximately produced per day

Answer 13

8L

Question 14

What happens to the lymph produced everyday

Answer 14

About half is reabsorbed into the lymph nodes

Question 15

How many lymph nodes are there in a young adult

Answer 15

About 450

Question 16

How many lymph nodes in the abdomen are chiefly associated with the mesenteries

Answer 16

250

Question 17

What are the lymph nodes in the abdomen chiefly associated with the mesenteries known as

Answer 17

Deep lymph nodes

Question 18

Give an example of superficial lymph nodes

Answer 18

Inguinal nodes located in and around the femoral triangle at the base of the lower limb

Question 19

Give an example of a primary lymphatic tumour

Answer 19

Hodgkins

Question 20

How does a secondary tumour form

Answer 20

As a result of metastasis from other sites

Question 21

How does lymphatic fluid drainage occur

Answer 21

Initially it occurs symmetrically from the limbs, head, neck and trunk
Deep lymphatic drainage will normally follow the routes of arterial supply
Eventually all the lymph congregates into 2 large lymph ducts which empty into the venous system at the jugular/subclavian junction

Question 22

How many lymphatic ducts are there

Name them

Answer 22

2
Right lymphatic duct
Thoracic duct

Question 23

What happens to the fat absorbed into the lymph from the small intestine

Answer 23

They drain to the SVC and eventually to the liver for absorption

Question 24

Where can lymphocytes be generated and mature

Answer 24

Thymus and Bone marrow (1)
Spleen (2)
Lymph nodes (2)
Peyer’s patches (2)
Tonsils
Lymphocytes

Question 25

What is the spleen

Answer 25

Largest lymphatic organ
It’s present in the upper left quadrant of abdomen (peritonised)
Contains large amount of blood, routinely discharged via smooth muscle action

Question 26

What occurs in the white pulp of of the spleen

Answer 26

The immune function where T (PALS) and B (germinal centres) cells are found

Question 27

What is found in the spleen

Answer 27

Red pulp

White pulp

Question 28

Where does lymph drainage NOT occur from

Answer 28

Epithelium
Cartilage
Bone
Central nervous system
Or from the majority of the spleen and liver