Lymphatics

Question 1

What are the components of the lymphatic and immune system

Answer 1

-lymph
-lymphatic vessels
-organs
-red bone marrow

Question 2

What is lymph

Answer 2

-lymph is blood plasma that filters out of capillaries

Question 3

What is the difference between lymph and interstitial fluid

Answer 3

-if the blood plasma is found in lymph vessels it is called lymph, if the blood plasma is found in between cells it is called interstitial fluid

Question 4

How is lymph formed

Answer 4

-from the interstitial fluid, as it enters the lymph vessels

Question 5

What are the major functions of the lymphatic and immune system

Answer 5

1. drains excess interstitial fluid
2. transports dietary lipids
3. carriers out immune response

Question 6

What is the function of T- cells

Answer 6

-also known as T lymphocytes, they are found in large numbers in lymph nodes
-function to attack viruses, fungi, bacteria, cancer cells, transplanted cells, and cause allergic and rejection reactions

Question 7

What is the function of B-cells

Answer 7

-also known as B lymphocytes, found in large numbers in the lymph nodes
-function to destroy bacteria and toxins

Question 8

What are lymphatic capillaries

Answer 8

-vessels found in spaces between cells
-closed at the terminal end
-unite to form lymphatic vessels
-subcutaneous vessels follow a similar pattern as veins
-viscera lymph vessels follow similar routes as arteries and form plexuses
-avascular tissues lack lymph vessels

Question 9

What causes fluid to enter the lymphatic capillary, and what prevents it from leaking back out

Answer 9

-interstitial pressure causes cells in lymphatic capillaries to separate and allow fluid in but fluid cannot leave

Question 10

How does edema affect the passage of fluid into the lymphatic capillary

Answer 10

-more interstitial pressure which opens a path further for more fluid to enter lymph capillary

Question 11

What is a lacteal

Answer 11

-lymphatic capillaries in the small intestines that take in dietary lipids and transports them to the blood

Question 12

Are there any tissues that lack lymphatic capillaries

Answer 12

-avascular
-cartilage
-epidermis
-cornea
-CNS
-parts of the spleen
-red bone marrow

Question 13

Describe the relationship between lymphatic capillaries, lymphatic vessels, lymph nodes, and lymphatic ducts

Answer 13

Lymph flows –> lymphatic capillaries –> lymph vessels –> lymph nodes –> lymphatic trunks –> thoracic duct (left) and right lymphatic duct –> blood at the junctions of the left and right internal jugular veins and subclavian veins

Question 14

Name two main lymphatic ducts, what does each do?

Answer 14

Thoracic duct: drains the left side of the head, neck, chest, left upper limb, and entire body inferior to the ribs

right lymphatic duct: drains the upper right side of the body

Question 15

Where do each of the main lymphatic ducts drain lymph into the circulatory system

Answer 15

-each duct drains lymph at the junction of the internal jugular and subclavian veins on the right and left

Question 16

What forces help lymph move through the lymphatic system

Answer 16

-the same forces that return venous blood to the heart and maintain lymph flow
1. skeletal muscular pump: muscle contractions compress lymph vessels
2. respiratory pump: during inhalations, lymph flows from higher pressure in the abdomen to lower pressure in the chest and valves prevent backflow during exhale

Question 17

What is the function of the primary lymphatic organ, and what are the primary lymphatic organs in the adult body?

Answer 17

-organs are sites where cells become immunocompetent
-they are red bone marrow and thymus

Question 18

What is the function of the secondary lymphatic organ, name the secondary lymphatic organs in the adult body.

Answer 18

-site of the immune response
-lymph nodes and spleen

Question 19

Describe the location of the thymus

Answer 19

-in the mediastinum between the sternum and aorta
-al the white dots in the picture are T cells
-the clear areas are thymic corpuscles that stain lighter and fewer T-lymph
-have swirls of keratinized epithelial cells
-corpuscles prevention of autoimmune response

Question 20

What is the function of the thymus

Answer 20

-develops/matures T cells to become immunocompetent, has its own barrier

Question 21

How does the thymus change as the human or other type of mammal ages

Answer 21

-active tissues atrophy and are replaced with fat

Question 22

Where are the lymph nodes located and what is their function

Answer 22

-scattered in groups
-mammary glands, axillae, and groin have large clusters of nodes
–filter lymph and houses B and T cells that destroy foreign substances as lymph filter through

Question 23

What is the function of the afferent and the efferent lymphatic vessels

Answer 23

afferent = carry lymph to nodes
efferent = carry lymph away from nodes

Question 24

location of the spleen

Answer 24

-found on the left side of the abdominal cavity between the diaphragm and stomach

Question 25

Name two kinds (colors) of tissue found in the spleen

Answer 25

-red pulp
-white pulp

Question 26

What is the function of the white pulp

Answer 26

-white pulp contains lymphocytes and macrophages to destroy blood-borne pathogens

Question 27

What is the function of the red pulp

Answer 27

-red pulp contains filled sinuses with RBC, macrophages, lymphocytes, plasma cells, and granulocytes
-function is to remove macrophages, RBC and platelets that are no longer useful, platelet storage, and fetal RBC production

Question 28

What are tonsils

Answer 28

-tonsils are lymph nodules in the nasal cavity, nasopharynx, oral cavity, and oropharynx
-they trap ingested/inhaled substances into crypts where B cells and T cells attack and destroy