Помогите пож с 3 заданием((( Текст прилагается

Immunity means resistance to disease.
It is provided by certain white blood cells which release antibodies and antitoxins intro the blood plasma.
The factors like antigens can stimulate white cells to produce antibodies and antitoxins.
When infection occurs, inflammation results, and part of this defensive reaction involves antibodies and antitoxins.
Some of antibodies and antitoxins can remain in the blood for whole life.
The acquired immunity doesn't occur for every type of microorganism.
It can be reproduced artificially in people who have never been infected by a particular microorganism.
It may be done by giving a non-immune person a dose of dead microorganism.
Dead microorganisms stimulate the host's body to produce antibodies and antitoxins against the particular microorganisms concerned.
If there has been no vaccination or prior exposure to disease, acquired immunity is not present.
Because of natural immunity some people are more resistant to disease than others.