A vaccine works by stimulating the immune system to produce antibodies without actually infecting someone with that disease. They trigger the immune system to produce its own antibodies as though the body has been infected with the disease. But a vaccine will not make someone immune to a disease, it will simply help the body be able fight the infection better.
Type of chocolate bar, size of it, surface it is placed on, etc
Controlled variables are anything that stay the same for both trials
In prophase is when they form
