Lecture #22 The Lymphatic System

Question 1

What lymphatic vessel is responsible for absorption and transport of ingested lipids?

Answer 1

Lymphatic vessels located in the villi of the gastrointestinal tact (GIT) known as LACTEALS are responsible for absorption and transport of ingested lipids.

Question 2

Contains nutrients, oxygen, hormones, and fatty acids, as well as toxins and cellular waste products, that are transported to and from cellular tissues

A.  Lymph
B.  Lymphatic vessel
C.  Lymph nodes
D.  Spleen
E.  Thymus

Answer 2

A. Lymph

Question 3

Serves as the site of T-lymphocyte maturation, development, and control

A.  Lymph
B.  Lymphatic vessel
C.  Lymph nodes
D.  Spleen
E.  Thymus

Answer 3

E. Thymus

Question 4

Monitors the composition of lymph, the location of pathogen engulfment and eradication, the immunologic response, and the regulation site

A.  Lymph
B.  Lymphatic vessel
C.  Lymph nodes
D.  Spleen
E.  Thymus

Answer 4

C. Lymph nodes

Question 5

Monitors the composition of blood components, the location of pathogen engulfment and eradication, the immunologic response, and the regulation site

A.  Lymph
B.  Lymphatic vessel
C.  Lymph nodes
D.  Spleen
E.  Thymus

Answer 5

C. Lymph nodes

Question 6

Transport lymph from peripheral tissues to the veins of the cardiovascular system

A.  Lymph
B.  Lymphatic vessel
C.  Lymph nodes
D.  Spleen
E.  Thymus

Answer 6

B. Lymphatic vessel

Question 7

What are primary lymphoid organs?

Answer 7

• bone marrow

- thymus

Question 8

What are secondary lymphoid organs?

Answer 8

• lymph node

- spleen

Question 9

What is a lymphatic nodule?

Answer 9

Collection of B lymphocytes

• Pale staining central region – germinal center
• When activated in presence of invading microorganism, B cells proliferate producing plasma cells- antibody producing cells
• Macrophages are also found in the germinal center

Question 10

What is the order of lymph circulation?

Answer 10

Lymphatic capillaries →Lymphatic vessels → Lymph nodes → Lymph trunks → Cisterna Chyli → Lymph ducts → Blood

Question 11

What is the location for the proliferation and maturation of T-cells?

Answer 11

Thymus

originate from the bone marrow

Question 12

What part of the thymus contains mainly immature T lymphocytes, is darker staining (due to tightly packed lymphocytes) and also contains special type of cells called Epithelial Reticular Cells (ERCs)?

Answer 12

Cortex

Question 13

_______________ establish a protective blood-thymus barrier that prevents the developing thymocytes from coming in contact with antigens.

Answer 13

Epithelial Reticular Cells (ERCs)

Question 14

Which part of the thymus contains more Epithelial Reticular Cells (ERCs)?

Answer 14

The medulla is lighter staining – due to less lymphocyte concentration. Also contains more ERCs.

Question 15

The thymus contains no afferent lymph vessels (unlike the lymph node). T/F

Answer 15

True

Question 16

Where are Hassal Corpuscles found?

Answer 16

Hassal Corpuscles (found in the medulla of the thymus)

Question 17

__________________ mature and differentiate in the bone marrow.

Answer 17

B lymphocytes develop

Question 18

Lymph nodes have no afferent lymph vessels. (T/F)

Answer 18

False, Lymph nodes have efferent and afferent lymphatic vessels

Question 19

What is the flow of lymph?

Answer 19

Lymph from afferent lymphatic vessels → Drain into sub capsular sinuses → From the suncapsular sinuses, lymph flow into the trabecular sinuses → Then to the medullary sinuses → And finally exit via the efferent lymphatics in the hilum of the lymph node.

Question 20

The spleen contains a cortex and medulla. (T/F)

Answer 20

Unlike the lymph nodes, contains no cortex or medulla

Question 21

What forms the Waldeyer’s ring?

Answer 21

the pharyngeal tonsil, palatine tonsil and lingual tonsil

Question 22

Where does the right lymphatic duct usually drain?

Answer 22

The right lymphatic duct usually drains into the right subclavian, at its junction with the right internal jugular vein.

Question 23

The right lymphatic duct drains lymph from which parts of the body?

Answer 23

• Upper right side of the trunk above the diaphragm (via the right bronchomediastinal trunk)
• Right upper limb (via right subclavian trunk)
• Right side of the head and neck (via right jugular trunk)

Question 24

What drains into the thoracic duct?

Answer 24

Collects and drains lymph from the lower part of the body below the diaphragm, left side of the trunk above the diaphragm, the left upper limb and the left side of the head and neck.

Question 25

Where does the thoracic duct drain?

Answer 25

It drains/empties into the left brachiocephalic vein.

Thoracic duct is the largest lymphatic vessel in the human body. It usually starts at the level of the 2nd lumber vertebra and extends to the neck.