BLOG 2: IMMUNE SYSTEM IN THE HUMAN BODY

GOOD MORNING DEAR BOYS.
MARK YOUR ATTENDANCE !!


Today we will achieve the following LEARNING OUTCOMES:
Students will be able to -

1. Understand & list the various organs that play a role in IMMUNE SYSTEM of our body.

2. Analyse the mechanism of how each work & what kind of responses are generated  by our body .


GENERAL INSTRUCTIONS 

1.Write your notes in your register.
2. There is 2  YouTube links sent along with this blog . Kindly watch it before reading the blog.

3. Ask your doubts ?


Let's Begin ...

WATCH THE YouTube VIDEO LINKS GIVEN BELOW:-


https://youtu.be/2n3AKrbU46Q

https://youtu.be/kjLwVqxwaIM

Immune System in the Body

The human immune system is composed of lymphoid organs, tissues, cells and soluble molecules like antibodies.

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Lymphoid organs:

Origin and/or maturation and proliferation of lymphocytes take place in these organs.

Primary Lymphoid Organs: Bone marrow and thymus are the primary lymphoid organs. Immature lymphocytes differentiate into antigen-sensitive lymphocytes in the thymus.

Secondary Lymphoid Organs: Secondary lymphoid organs are; spleen, lymph nodes, tonsils, Peyer’s patches of small intestine and appendix. Interaction of lymphocytes with antigen takes place in secondary lymphoid organs. After that, lymphocytes proliferate to become effector cells.

Bone marrow is the main lymphoid organ where all blood cells (including lymphocytes) are produced. Both bone marrow and thymus provide micro-environments for the development and maturation of T-lymphocytes. Spleen mainly contains lymphocytes and phagocytes. Spleen acts as a filter of the blood by trapping blood-borne microorganisms. Spleen also has a large reservoir of erythrocytes.

Lymph Nodes: Lymph nodes are small solid structures. They are located at different points along the lymphatic system. Lymph nodes trap microorganisms or other antigens which happen to get into the lymph. Antigens trapped in lymph nodes are responsible for activation of lymphocytes present there.

Mucosal Associated Lymphoid Tissue: Lymphoid tissue is also present within the lining of the major tracts. This is called mucosal associated lymphoid tissue (MALT). It constitutes about 50% of the lymphoid tissue in human body.

THAT'S IT FOR TODAY .

I WILL SEE YOU TOMORROW ACCORDING TO DAY 5 TIME TABLE .

NO HOMEWORK TODAY