Antigens are molecules that the immune system recognizes as foreign to the body.
Children are born with an immature immune, or defense, system.
Antigens are molecules that the defense system recognizes as foreign to the body.
What are molecules that the defense system recognizes as foreign to the body?
A. Allergies
B. lungs
C. antigens
D. bacteria
E. parasites
F. atoms
G. red blood cells
H. acetic acid