Lymphatic System

Question 1

Where is the Lymphatic System not found?

Answer 1

Lymphatic vessels are found everywhere except in Cartilage, Bone, epidermis, and CNS

Question 2

What kind of system is the Lymphatic System?

Answer 2

The Lymphatic System is an open system meaning there is no pump for circulation. The fluid movement instead is caused by the contraction of muscles.

Question 3

What is the Lymphatic System?

Answer 3

Many connected tubes that collect and deliver H20 and dissolved solutes from the interstitial fluid to the circulatory system ducts and ultimately to the heart. It also takes part in immune system surveillance

Question 4

What is the structure of the lymphatic system?

Answer 4

• The lymphatic system is composed of vessels that have three layers similar to veins.
• The vessels move lymph toward the heart in one direction, using valves to prevent backflow.
• The lymph moves into lymph nodes that deposit the lymph into blood which then makes its way to the heart
• Lymphocytes are spread throughout the body, but are very abundant around the neck, axilla, groin, and around major vessels.

Question 5

What is a lymph node?

Answer 5

• Lymph nodes are specialized structures that are filled with white blood cells. When you are sick these swell up with white blood cells to help fight infection.
• Lymph nodes also contain cells such as: T and B lymphocytes, plasma cells, macrophages, and dendritic cells
• Lymph nodes are the major sites of B and T cell lymphocytes. These nodes act as filters for foreign particles and malignant cells. B-Cells create antibodies here and they leave the lymph nodes to circulate the body.

Question 6

What are Peyer’s patches?

Answer 6

• AKA: GALT (Gut Associated Lymphoid Tissue)
• Peyer’s Patches are lymphoid aggregates found in the ileum of the small intestine that monitor intestinal bacterial populations as well as defending us against pathogenic intestinal bacteria

Question 7

What are Lymph’s characteristics?

Answer 7

Lymph is very similar to blood plasma, and it is a clear to white fluid (the white color is due to the presence of lipids when it is in the GI tract)

Question 8

What is an immunoglobin?

Answer 8

Immunoglobin is an antibody on the move throughout the body.

Question 9

What is the humoral immune system composed of?

Answer 9

The humoral immune system is made up of B-Lymphocytes, which function to create antibodies. These B-Lymphocytes mature in the bone marrow

Question 10

What is the Cell-Mediated Immune system composed of?

Answer 10

The Cell-Mediated Immune system is composed of T-Lymphocytes which function to kill foreign or intracellular infected cells. They also create cytokines. T-Lymphocytes mature in the Thymus.

Question 11

What are the primary immune organs?

Answer 11

The primary immune organs are Bone and Thymus

Question 12

What are the secondary immune organs?

Answer 12

The secondary immune organs are the lymph nodes, spleen, and certain cells of the respiratory and GI tract.

Question 13

What is the Thymus?

Answer 13

• The Thymus is a primary immune organ
• It is located just below the breast bone at the level of the heart
• After puberty it begins to shrink, and removal of the organ as an adult has little effect on the body. By age 75, this organ turns into fatty tissue.
• It is essential for the development of immune cells in newborns
• It produces several growth factors that cause the proliferation and differentiation of T-Lymphocytes.
• It produces the hormone thymosin that helps T-Lymphocytes develop, as well as the hormones Thymopoietin and Thymulin.
• Nearly all of our T-Cells are made before puberty

Question 14

What is thymosin?

Answer 14

Thymosin is a hormone that is made by the Thymus that helps in the development of T-Lymphocytes

Question 15

What is DiGeorge’s syndrome?

Answer 15

DiGeorge’s syndrome is the congenital failure of the thymus to develop.

It means the body doesn’t have any T-Lymphocytes, so the body dies at an early age.

Question 16

What is the Spleen?

Answer 16

• The Spleen is an organ that acts as a blood reservoir and essentially a large Lymph node (contains T-Cells, B-Cells, and Macrophages
• It contains the largest accumulation of lymph tissue in the body
• It’s a graveyard of old RBCs. They lose their sialic acid residues on their surface, exposing galactose which allows them to be phagocytosed. The iron and protein portions of hemoglobin are able to be recycled.
• Produces B and T-Lymphocytes
• Located in the upper left part of the abdomen
• Many platelets are stored here which are involved in blood clotting.
• If lost by illness or accident, the functions of the spleen can be done by the liver, bone marrow, and lymph nodes.

Question 17

What is BALT?

Answer 17

BALT is Bronchus-associated lymphatic tissue, located in the walls of the bronchi. This is similar to GALT (Peyer’s Patches)

Question 18

What are Tonsils?

Answer 18

Tonsils are aggregates of lymphatic tissue that help us guard against pathogens.

Located lingual, palatin, and pharyngeal