What is an antigen and antibody? and what are their difference(s)?

There are a total of 5 types of antibodies, each of which is different. They are IgA, IgE, IgG, IgM, and IgD.

IgA protects the surfaces of the body which receive exposure to foreign, outside substances.

IgE causes a reaction in the body against foreign substances, including animal dander, pollen, and fungus spores. These antibodies are part of allergic reactions to some poisons and certain medications. Those with allergies tend to have high quantities of this type of antibody.

IgG plays a key role in fighting infections of a bacterial or viral nature. These are the only antibodies that are able to cross the placenta of a pregnant woman, offering protection to the fetus while still in utero.

When an infection occurs, IgM antibodies are the very first type of antibodies to be made as a response. They will lead to other cells in the immune system destroying foreign substances.

Experts are still unclear as to what exactly IgD antibodies d

nucleus

would be most reasonable answer tbh