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

In the water, why the water is important in all the people in the world

why the water is important in all the people in the world

Availability of nutrients, Availability of Nutrients: The nutrients  in...

Availability of Nutrients: The nutrients  in  the upper layers of water are constantly being taken up by  the phytoplankton, who are the producers, and then these pass on to th

Thermal veiocity, what is thermal velocity ofa material..

what is thermal velocity ofa material..

Life cycle of the sun and plot it on an hr diagram, 1. What is the Solar Ne...

1. What is the Solar Neutrino problem, and what are the possible resolutions of it? Which of these resolutions is now believed to be the most likely explanation? 2.What is the m

Factor for hypothalamic control of anterior pituitary gland, Define Factors...

Define Factors for hypothalamic control of anterior pituitary gland Thyrotropin Releasing Factor (TRF) which causes release of TSH. Corticotropin Releasing Factor (CRF

Explain in-vitro detection of antigen-antibody interaction, Explain In-Vitr...

Explain In-Vitro Detection of Antigen-Antibody Interaction Any infection caused, requires a proper treatment. This can be achieved only if the correct organism is identified. S

Lead times of scientific development, Lead Times of Scientific Development:...

Lead Times of Scientific Development: When we compare the current status of scientific development and technological fall-out from the same, we find that the lead time of scien

Solid waste, Solid waste Solid waste in some cases can be a resource. A...

Solid waste Solid waste in some cases can be a resource. A good example is the factory at Yokohama in Japan which is engaged in converting waste paper into toilet paper. In our

Semiconductor devices and their uses, Semiconductor Devices and their Uses:...

Semiconductor Devices and their Uses: If a junction  is formed between a p-type and an n-type'semiconductor,  the device called a p- n  junction diode acquires a peculiar pppen

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