Your immune system uses a huge army of defender cells - different types of white blood cell. You make about 1000 million of them every day in your bone marrow. Some of these cells, called macrophages, constantly patrol your body, destroying germs as soon as they enter. This is your 'natural' or inborn immunity. But if an infection begins to take hold, your body fights back with an even more powerful defence of T- and B-cells. They give you acquired immunity, so that the same germ can never make you as ill again.
Answer:
8.j
5. i
Explanation:
these are the two that i know off the top of my head
People who are sad because of some one that died
People who have went through a broken heart
Orphans
Homeless
People who became hit by bad news
People who are lonely
People who never have someone to cheer them up.
Bone, which is made of collagen, which is strenghtened by calcium phosphate
