IGA is secreted into the bloodstream, whereas is secreted into mucus such as gastrointestinal fluid, colostrum, saliva, tears, and sweat:

is secreted into the bloodstream, whereas is secreted into mucus such as gastrointestinal fluid, colostrum, saliva, tears, and sweat:

a. Monomeric IgM; pentameris IgM

b. Monomeric IgA; dimeric IgA

c. Monomeric IgA; dimeric IgM

d. Dimeric IgA; monomeric IgA

b. Monomeric IgA; dimeric IgA

Explanation:

IgA is a class of antibodies that are found mainly in body secretions. In sweat, tears, saliva, mucus, breast milk, and gastrointestinal secretions, IgA is secreted as a monomeric antibody. Smaller quantities of this class of antibodies are also present in blood and lymph. However, IgA is present in a dimeric form in the bloodstream. It makes up 10–15% of all antibodies in the blood. The main function of this class of antibodies is to give localized protection of mucous membranes against bacteria and viruses.

bacteria could be both, harmful and to us. harmful bacteria could make us sick and probably even by getting the chances of getting a disease, but good bacteria fight it off with your immune system. there is always bacteria everywhere we go. we need to make sure to wash our hands after using the restroom, before eating, after eating, after petting an animal too. so you see, bacteria is everywhere and is harmful or . i hope this . : ) : ) : )