organs of the immune system

Question 1

what are lymphoid organs?

Answer 1

parts of the immune system that play a crucial role in the body’s defense against infections and diseases.

Question 2

what are the lymphoid organs responsible for?

Answer 2

production and maturation of lymphocytes,

Question 3

what are the key lymphoid organs?

Answer 3

bone marrow
thymus
spleen
lymph nodes
Tonsils and Adenoids
Peyer’s Patches

Question 4

summarise the primary lymphoid organs- bone marrow

Answer 4

bone marrow site of generation of all circulating blood cells in an adult including immature lymphocytes and is site of b cell maturation

site of differentiation and maturation of WBC

site of immune response of b cells specifically in secondary immune response

Question 5

summarise lymphoid organs - thymus

Answer 5

both t cells and b cells are ‘born’ in the bone marrow

• b cells can mature in the bone marrow whereas t cells have to mature in the thymus (where they move to)

Question 6

what happens to immature lymphocytes?

Answer 6

become committed within the primary lymphoid organs

Only after maturation has occurred that cell is IMMUNOCOMPETENT

Question 7

what are the secondary lymphoid organs?

Answer 7

adenoids
peyers patches
appendix

Question 8

what is the function of the lymph nodes?

Answer 8

contain high concentrations of leukocytes that filter out microbes and toxins

Question 9

what is the function of spleen>

Answer 9

of the blood circulatory system has the same function as the lymph nodes

Question 10

how can the lymph nodes and the spleen may be affected?

Answer 10

infected by the organisms that have collected
during filtration

Question 11

summarise the lymphatic system? 1/3

Answer 11

As blood circulates under pressure, plasma seeps through thin walls of capillaries.

Question 12

summarise the lymphatic system? 2/3

Answer 12

Much of this fluid returned to blood but some enters lymphatic system, which is referred to as “lymph”.

Question 13

what is the structure of a lymph node?

Answer 13

outer cortex- filled with lymph follicles

outer edge of follicle contains more t cells

inner germinal center is the site of b cells prolifeeration

Question 14

summarise the lymphatic system? 3/3

Answer 14

When a foreign antigen gains entry to the tissues, it is picked up by lymphatic system and taken to lymph nodes that trap the antigen

Question 15

what is the inner medulla of the lymph node responsible for?

Answer 15

medullary cords of the lymphcytes, macrophages, plasma cells (activated b cells)

Question 16

what can the fibres of the lymph node act as?

Answer 16

net to catch any debris or cells that are present in the lymph

Question 17

reticular fibres?

Answer 17

Macrophages and lymphocytes attack and kill any microbes caught in the reticular fibers.

Question 18

what is extravasation?

Answer 18

immune cells travel back and forth from the blood and lymph CS and interact with extra vascular tissues in the process

Question 19

what is extravasation? simple

Answer 19

escape of fluid, cells, or other substances from blood vessels into surrounding tissues

Question 20

what can cause extravasation?

Answer 20

including inflammation, injury, or certain medical procedures

Question 21

what is lymph?

Answer 21

a fluid containing
-water
-sugars
-wbc
-protein

Question 22

what are lymph vessels

Answer 22

carry lymph within the lymphatic system

lymph capillaries are the smallest of the lymph vessels

Question 23

how do leukocytes travel from one system to another

Answer 23

Lymph carrying antibodies
and immune cells collect in
thoracic duct where the
lymph empties back into the
blood circulatory system

Question 24

what happens when the lymphatic system goes wrong?

Answer 24

lymphatic filariasis- symptoms` include swelling and enlargement of the arms and legs

Question 25

People with elephantiasis have what?

Answer 25

impaired immune function due to damage to the lymph system

Question 26

summarise the spleen?

Answer 26

largest lymphoid tissue

Question 27

what are the functions of the spleen

Answer 27

Filters out older RBCs
Responds to Antigens in circulatory system
Produces activated B cells
Stores platelets
In fetus: site of haematopoiesis

Question 28

what happens when the spleen gets damaged?

Answer 28

; splenectomy increases risk of bacterial infection

Question 29

describe the tonsils?

Answer 29

masses of lymph tissue designed to filter tissue fluid, not lymph

Question 30

what is tissue fluid?

Answer 30

Tissue fluid, also known as interstitial fluid or extracellular fluid, is a clear, colorless fluid that surrounds the cells within tissues.