Define specific defence mechanism, Science

Assignment Help:

Define Specific Defence Mechanism

In the section on white blood cells, we learnt that whenever a germ or infection enters our body, the WBCs snap to attention and destroy the culprit. How does a white blood cell know what to attack and what to leave alone? Why doesn't a white blood cell attack every cell in the body? The answer to these questions lies in the discussion below.

The specific defence mechanism provides protection against specific foreign materials. The important characteristic is that its cells (lymphocytes) have an ability to recognize body's own cells and macro molecules (self) from those which are foreign invaders (non self ). It tolerates the 'self' but destroys the 'non self'. The lymphocytes bearing receptor is specific for self i.e. molecules already present in the body, are either made non-functional or destroyed by programmed cell-death known as apoptosis. The lymphocytes that react to non self i.e. foreign molecules are left to function in immune responses.

So, you realize that there is a system built into all of the cells in our body that marks the cells in our body as "self '. Anything that the immune system finds that does not have these markings (or that has the wrong markings) is definitely "not self" and is therefore a fair game. This system is called the Major Histocompatibility Complex (MHC).


Related Discussions:- Define specific defence mechanism

Carbon atoms of fatty acids, Carbon atoms  of  fatty acids are  numbered...

Carbon atoms  of  fatty acids are  numbered  from  carboxyl  carbon. Various conventions are  used  to  indicate the  position of double bonds  in  the fatty acid molecules. Like,

Particles, 1.) Imagine that you are a particle inside an ice cube. You were...

1.) Imagine that you are a particle inside an ice cube. You were placed into a glass of lemonade to cool it down. The lemonade has now been drunk and you have been left in the glas

#title.cognitive neuroscience techniques, I am interested learning about a ...

I am interested learning about a cognitive neuroscience technique in treating addiction and substance abuse.

Biogas, Biogas You may have heard of the use of cattle dung for produ...

Biogas You may have heard of the use of cattle dung for production of biogas which is used for cooking. Water weeds like water hyacinth, water lettuce, salvinia, hydrilla, du

Differential survivability, three adaptations that help humans have differe...

three adaptations that help humans have differential survivability, and three adaptations that help humans have differential fecundity

An experiment with a loop of thread, An experiment with a loop of thread ...

An experiment with a loop of thread Rinse a dinner plate methodically and then fill it with water. Make a loop with thread, open it a little and float it on the water. Touch th

Define white blood cells (wbcs), Define White Blood cells (WBCs) WBCs a...

Define White Blood cells (WBCs) WBCs are also called leukocytes, as they are colourless. They are the army of the human body. Whenever a germ or infection enters our body, the

Explain the functions of parathyroid gland, Explain the Functions of Parath...

Explain the Functions of Parathyroid Gland The main function of the parathyroid gland is to regulate the calcium levels in our body so that the nervous and muscular functions (

Public health policy, Ascan you promise a perfect job k question #Minimum 1...

Ascan you promise a perfect job k question #Minimum 100 words accepted#

Explanation of preparation of patient for use of enema, Question 1. Des...

Question 1. Describe the factors influencing the development of nosocomial infections 2. Explain briefly the standard precautions taken for infection control 3. Explain h

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd