If the farmer were to breed both of the two different types of cattle he would have a hybrid type of new cattle with both traits :)
Do you mean when nucleotides get damaged or when they match to each other incoreectly? (which cuases mutants) Specialized Enzymes repair, different one respond to help different types of damage. Detail the question more, maybe then i can help more.
A vaccine can help keep people healthy and protect them from a certain virus. For example people in the United States get the flu shot when they get this shot the vaccine wont magically get rid of the virus but rather help them fight it off and protect them in the future if they keep up to date getting the vaccine
The studying a system of word used things in a particular discipline called terminology
