The Lymphatic System and Spleen

Question 1

What is the role of the Lymphatic system

Answer 1

The lymphatic system is the drainage system of the body

Question 2

What is the role of the lymph?

Answer 2

(watery fluid collected from tissues)

This fluid contains antibodies and lymphocytes. It also contains bacteria that will get filtered out by the lymphatic system. The lymph is transported by the nodes and vessels.

Question 3

What is the role of the lymphocytes?

Answer 3

Lymphocytes are a type of white blood cell. There are 2 types, B cells and T cells. B cells produce the antibodies which are important for killing pathogens. T cells identify infected cells and get rid of them

Question 4

What is the role of the Lymphatic vessels?

Answer 4

Lymphatic vessels are similar to blood vessels. They carry the lymph around the body. They are very thin.
Have numerous cup-shaped valves (like veins) to ensure that lymph flows towards the thorax.
Eventually, form 2 large ducts; The thoracic duct and the right lymphatic duct, which empty lymph into the subclavian veins.

Question 5

What is the role of the Lymph nodes?

Answer 5

Lymph nodes are important because they filter out the harmful substances. They contain white blood cells to fight pathogens in the lymph fluid. They are small lumps of tissue.

Question 6

What is the role of tonsils?

Answer 6

They are located in the throat and palate and they stop pathogens from entering the body. They contain white blood cells.
3 groups
Pharyngeal (adenoids)
Palatine
Lingual

Question 7

What is the role of the spleen?

Answer 7

It filters the blood and removes the damaged red blood cells and stores the iron.
It also stores blood and will release the blood into the circulatory system in an emergency such as extreme blood loss (erythropoiesis).

Largest of the lymph organs.
Lies in left hypochondriac region.
Served by 
\+ Splenic Artery – branch of Coeliac artery
\+ Splenic Vein – branch of portal vein
\+ Lymph vessels
\+ Nerves

Question 8

What is the role of Thymus Gland?

Answer 8

Produces progenitor cells which will mature into T-cells. The T-cells will destroy infected cells or cancerous cells.

2 lobes joined by areolar tissue.
Enclosed by a fibrous capsule, that divides it into lobes.

Question 9

What is the Thoracic Duct?

Answer 9

Begins at cisterna chyli – dilated lymph channel in front of L1 and L2.
40 cm long
Opens into the Left subclavian vein at root of neck.
Drains both legs, pelvis, abdomen, left half of thorax, head, neck and left arm.

Question 10

What does the Right Lymphatic Duct do?

Answer 10

1 cm long
Lies in root of neck and drains into Right subclavian vein
Drains right half of thorax, head, neck and right arm.

Question 11

How does the lymph move?

Answer 11

The lymph doesn’t have a pump so it has many valves to prevent backflow and muscular walls contract to help push lymph against gravity. Also, pressure from surrounding tissue such as muscle contraction is needed to help push lymph along.

Question 12

Lymphatic organs and tissues?

Answer 12

Lymph nodes
Tonsils
Spleen
Thymus

Question 13

Structure and location of lymph nodes?

Answer 13

Bean shaped or oval.
Pin head -almond in size.
Often in groups of either deep or superficial.
Superficial ones – neck, arm pit, groin.
Lymph pass through 8-10 nodes before draining back into the venous circulation.

Outer capsule of fibrous tissue.
Reticular cells which make a fibrous structure within the node.

Question 14

Mucosa – Associated Lymphoid Tissue (MALT)

Answer 14

Have no capsule
Do not filter lymph
Not exposed to diseases spread by lymph
Peyer’s Patches – small intestine

Question 15

Structure of the spleen?

Answer 15

Oval
Peritoneum covers the anterior surface
Covered with fibro-elastic capsule and dips into the organ forming trabeculae. 
Splenic pulp lies in between.
Red pulp – filled with blood
White pulp – filled with lymph