2.  allergy is
hypersensitivity to a
ordinary material in
the environment or
to certain drugs
 allergens are the
substance that
causes allergy

3.  The immune system of the body is
designed to fight off foreign substances,
also known as antigen. The antigen
triggers the immune system to produce
antibodies or immunoglobulin. There are
five types of immunoglobulin, can
abbreviated as Ig, such as IgA, IgM, IgG,
and IgE. But, the over production of
immunoglobulin E or IgE is the reason for
an allergic reaction.

4.  is also known as
urticaria
 it is caused by an
allergic reaction
 it could appear
anywhere in the skin
as swollen, pale red
bumps or wheals
(plaques)

5.  can be itchy, burn or
sting
 can be in a size of a
pencil eraser to a
the size of a dinner
plate
 could last for hours or
up to a day before
fading

6.  also known as
immunization
 it is an exposure to a
weakened or dead
pathogens to
stimulates the immune
system and produces
antibodies, so when
the person is later
exposed to a certain
kind of live pathogen,
he or she will not get
sick