WEEK 7 LYMPHATIC SYSTEM FINISHED

Question 1

What is the function of lymphatic vessels?

Answer 1

Assist the C/V system by removing fluid from the tissue spaces of the body, returning fluid to the blood.

Question 2

What is lymphatic tissue? What is the function of lymphatic tissue?

Answer 2

A type of connective tissue with large numbers of lymphocytes (esp useful for the defence against bacteria and viruses)

Question 3

What are the 4 functions of the lymphatic system?

Answer 3

Protection and maintenance of the internal fluid environment of the body by producing, filtering and converting lymph and producing various blood cells

Collects surplus tissue fluid

Absorbs and transports fat (small intestine)

Defence

Question 4

Describe lymph.

Answer 4

Clear colourless fluid found in the lymphatics. This is the name given to tissue fluid once it has entered a lymph vessel.

Question 5

Where are lymph capillaries usually found? What are they? What are they composed of

Answer 5

Where there are blood capillaries. Form a closed network but with a larger mesh. They are formed by simple endothelial tubes with porous junctions where interstitial fluid, proteins, microorganisms and absorbed fats can easily enter.

Question 6

Where are lymph capillaries NOT found

Answer 6

Epithelium, epidermis of skin, cartilage, bone, bone marrow, thymus, internal ear, eyeball, placenta, cornea, teeth, CNS or other tissues devoid of blood vessels.

Question 7

What are sinusoids? Where are they found

Answer 7

Found in the spleen and liver, irregular spaces between cells where blood passes. They act as the sole drainage structures of these 2 organs

Question 8

What is the function of lymph vessels? What is the diameter of a normal lymph vessel?

Answer 8

Drain the lymph capillary networks. 1/2 to 1 mm diameter

Question 9

What are lymphaticovenous communications?

Answer 9

Communications between lymphatics and veins.

Question 10

What is the general rule in regards to which lymph vessels follow which blood vessels?

Answer 10

Superficial follow veins

Deep follow arteries

Question 11

What are lymph nodes? What colour are they? What shape are they?

Answer 11

A structure through which lymph passes through on its way to the venous system. Found clustered along lymphatic vessels they can vary greatly in size. Packed with lymphocytes and phagocytic cells to help purify the lymph.

They are pink in real life, brown in cadavers.
Bean shaped with a fibrous connective tissue capsule

Question 12

What are the 2 vessels that enter and exit lymph nodes?

Answer 12

Afferent vessels flow into the nodes

Efferent vessels flow out of the nodes

Question 13

What is the function of lymph nodes?

Answer 13

Filters lymph
Factors for lymphocytes
Contain antibodies
Bacteria and cancer cells may be stopped and destroyed by phagocytes in the lymph but can sometimes acts as a pathway for cancer spread.

Question 14

What is lymphoid tissue?

Answer 14

Collections of enormous numbers of migratory and semimigratory lymphocytes and play an important role in immune reactions in the body

Question 15

Where can lymphoid tissue be found

Answer 15

Lymph nodes
Tonsils
Follicles in the intestine
Appendix
Thymus
Spleen

Question 16

What are the 3 main paired lymph trunks?

Answer 16

Jugular - accompanies internal jugular vein in the neck

Subclavian - accompanies subclavian vein in the upper limb

Bronchomediastinal - from the thoracic viscera

Question 17

Where do the 3 paid lymph trunks end? Where do they pass into?

Answer 17

Either separately or together near the angle between the internal jugular veins and subclavian veins.

They pass into the right lymphatic duct or thoracic duct.

Question 18

What region does the right thoracic duct drain? What is the exception from this region? What is the rate of flow from the thoracic duct?

Answer 18

Drains the lower extremities, abdomen, pelvis, left thoracic region, left upper extremity, left head and neck

Rate of flow from the thoracic duct in the general circulation is around 125ml her hour during normal exertion

Question 19

Describe the thoracic duct? Length, location, begins with the convergence of what?

Answer 19

38-45 cm long, 3mm in diameter

Lies anterior to the L1/2 vertebra, between the right and left crus of the diaphragm and aorta.

Begins with the convergence of the main lymphatic ducts of the abdomen.

Question 20

What is the cisterna chyli? Where does the travel?

Answer 20

The thoracic duct in some people looks like a mall thin walled sac, which gets calls the cistern chyli. It varies in size and shape.

It ascends though the aortic hiatus and then passes into the mediastinum. It then ascends through the thorax and enters the junction between the left internal jugular and left subclavian vein.

Question 21

How long is the thoracic duct?

What part of the body does it drain?

Where does the drain into?

Answer 21

1.25cm long

Drains the right upper extremity, right thoracic region, right head and neck.

It drains the 3 lymphatic trunks in the upper quadrant to the junction of the right internal jugular and right subclavian veins.