ANATOMY

Detailed explanation-1: -Pathogens have molecules called antigens on their surface. Antigens provide a unique signature for the pathogen that enables immune system cells to recognize different pathogens and distinguish pathogens from the body’s own cells and tissues.

Detailed explanation-2: -Each pathogen is made up of several subparts, usually unique to that specific pathogen and the disease it causes. The subpart of a pathogen that causes the formation of antibodies is called an antigen. The antibodies produced in response to the pathogen’s antigen are an important part of the immune system.

Detailed explanation-3: -A type of white blood cell called a lymphocyte recognises the antigen as being foreign and produces antibodies that are specific to that antigen.

Detailed explanation-4: -Summary: The innate immune system constitutes the first line of defense against invading microbial pathogens and relies on a large family of pattern recognition receptors (PRRs), which detect distinct evolutionarily conserved structures on pathogens, termed pathogen-associated molecular patterns (PAMPs).

Detailed explanation-5: -When the body senses foreign substances (called antigens), the immune system works to recognize the antigens and get rid of them. B lymphocytes are triggered to make antibodies (also called immunoglobulins). These proteins lock onto specific antigens.