Answer:
A vaccine activates our immune system without making us sick. Many dangerous infectious diseases can be prevented in this simple and uncostful
drug .Vaccines have eliminated some of the most dangerous, fatal diseases in human history.
Examples of a scientific theory
Scientific theories are testable and make falsifiable predictions. They describe the causes of a particular natural phenomenon and are used to explain and predict aspects of the physical universe or specific areas of inquiry (for example, electricity, chemistry, and astronomy).
Answer:
A. 2 cells are made from one cell
Gametes
gametes is another word for sex cells