SUBMITTED TO – MR. VIKAS DIXIT

MADE BY –

RAHUL TRIPATHI

CLASS – XII

ROLL NO - 34

P.O – VIDUTNAGAR

PIN – 224238

A state of having sufficient biological defenses to avoid infection, disease, or other unwanted biological invasion.

Capability of the body to resist harmful microbes from entering the body.

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CONTENTS PAGE NUMBER IMMUNITY 5

FLUID SYSTEM 6GRANULOCYTES 7

AGRANULOCYTES 8LYMPHOCYTES 9

DEFENCE MACHANISM 10TYPES OF IMMUNITY 11INNATE IMMUNITY 12

FIRST LINE OF DEFENCE 13ADAPTIVE IMMUNITY 14

NATURAL ADAPTIVE IMMUNITY 15ACTIVE ACQUIRED IMMUNITY 16

MUCOSAL IMMUNITY 17TYPES OF MALT 19

IMMUNITY CONFERRED BY VACCINES 20SOME INTERESTING FACTS 21

BIBLIOGRAPHY 22THANK YOU PAGE 23

This is to certify that Rahul Tripathi and of class XII has successfully completed this Biology project on the topic “IMMUNITY” prescribed by Mr. Vikas Dixit Sir, during academic session 2012-2013 as per the guidelines issues by Central Board of Secondary Education.

Mr. Vikas Dixit External Examiner

(P.G.T BIOLOGY)

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Immune system

Innate immunityAdaptive immunity

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Granulocytes

Neutrophils: Neutrophils defend against bacterial or fungal infection , have a multilobed nucleus. The life span of a circulating human neutrophil is about

5.4 days.

Eosinophils: Eosinophils primarily deal with parasitic infections. Eosinophils are also the predominant inflammatory cells in allergic reactions. They have a bi-lobed nucleus.

Basophils: Basophils are chiefly responsible for allergic and antigen response by releasing the

chemical histamine causing vasodilation.

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Agranulocytes

Lymphocytes: common in the lymph system and of three types: B cells, T cells

and natural killer cells.

Monocytes: they present pieces of pathogens to T cells so that the pathogens

may be recognized again and killed. Monocytes eventually leave the bloodstream to become tissue

macrophages.

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Defense mechanisms

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Types of immunity

Immunity

Innate

Adaptive

Natural

Artificial

Passive(matern

al)

Active(infectio

n) Passive(Ab

transfer)

Active(Immuniz

ation)

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Innate immunity (first line of defense)

Innate immunityAnatomical barriersInflamma-tionComple-ment systemCells of innate immune responseInterferonsLactoferrin and transferrin

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First line of defense

Adaptive ImmunityHumoral respons

e

Cell- mediate

d response

Extra cellular microbes

B lymphocytes

Elimination of microbes

Phagocytosed microbes in macrophage

Dendritic cells display antigen to T cells Intracellul

ar microbes within infected cell

T cells release cytokines

Activation of macrophage to kill microbes

Lysis of infected cell

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Natural adaptive immunityPassive ( maternal)

Acquired ImmunityPassive

Artificial adaptive immunity

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Pathogen enters body

Memory Th cells activate Killer T

cells.

Igs coat the pathogen before

symptoms appearopsonization

Active killer T cells phagocytose

antigen.

Pathogen encounters memory B cells and

memory helper T (Th)cells

Memory Helper T cellsMemory B cells

Memory B cells forms plasma

cells which release

immunoglobins (Igs)

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Mucosal Immunity

The mucosal immune system protects the internal surfaces of the body

The mucosal immune system ㆍ GI tract ㆍ Respiratory tract ㆍ Urogenital tract ㆍ exocrine glands associated with these organs

In a healthy human adult, this local immune system contributes almost 80% of all immunocytes.

These cells are accumulated in, or in transit between, various mucosa-associated lymphoid tissues (MALT), which together form the largest mammalian lymphoid organ system.

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Composition of MALT

Macrophages

Ig A and Ig G

T cellsB cells

Plasma cells

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Types of MALT: Depending in the region

it is present

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Immunity conferred by vaccines

• Positive events of the day seem to have a stronger helpful impact on immune function. Having a good time on Monday still had a positive effect

on the immune system by Wednesday.

• The frequent hand washing can break down the natural oils on the skin that serve as the first line (or layer) of defense for the immune system.

• Studies show that people who lack humor in their lives tend to have less protective immune responses.

• While the body needs some sunlight to produce vitamin D, too much sunshine can suppress the immune system.

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To make this project I have taken source from the following books:-

1. Ramesh Gupta2. Biology N.C.E.R.T

I have taken source from internet too , and taken help of our biology teacher Mr. Vikas Dixit sir.

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We would like to thank our Biology sir Mr. Vikas Dixit, who provided us this opportunity to make a project on “IMMUNITY” which really helped us to understand the concepts of Immunity of our body.

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