Question

What is innate immunity? Mention any two types of innate immunity barriers.

Answer 1

Hint:Immunity is the capability of any multicellular organism to resist any pathogen(foreign particle that can cause harm to the body). It is a complex biological system called the immune system in which the body recognizes the entry of any pathogen and works against it in order to eliminate it from the body.

Complete Answer:
Innate immunity:
Innate immunity is the non specific immunity.
It comes into play immediately or within some hours of entry of any antigen or pathogen to the body.
This type of immunity consists of physical , chemical and cellular response against the pathogen.
The main purpose of innate immunity is to immediately prevent the spread of any foreign particle in the body.It is a first line defense system of our body.

Two type of innate immunity barrier are-
->Physical barriers
->Biochemical barriers

Physical barriers:
Physical barriers of the immune system include skin and mucous membranes.
Skin as a physical barrier – Skin avoids the entry of any pathogen or antigenic molecule to enter in the body. Skin has an external layer of dead cells that is called a cuticle which is impermeable to many infectious agents and can not pass through skin. But any burn or injury in the skin can become a problem because from here the infectious agent can enter the body of an individual.
Mucus membrane as a physical barrier – Mucus membrane is present in the respiratory system and digestive system. The antigenic molecules get attached to that mucus and hence cannot enter the body. This infectious agent containing mucus in several forms such as cough can be removed out from the body.
Biochemical barriers:
Biochemical barriers of the innate immune system include many enzymes and acids. When any antigenic molecule passes through the skin may be from the injury part then it has to face the biochemical barriers inside the body.
Enzymes as biochemical barriers – Enzymes also can eliminate any pathogen from the body, For example – lysozyme in saliva, tears etc.
Acids as biochemical barriers – Acids like lactic acid and some fatty acids are bactericidal (that means they can kill the bacteria). These acids are the secretions of sweat and sebaceous gland.


Note:The presence of the immune system in the body of any organism is too important. Because the immune system protects the body from the attack of many bacteria, viruses and other microorganisms also. And it helps us to remain healthy.