What is a prophage? What is its role in the lysogenic cycle?

The image shows embryos of three vertebrate classes

How are mutations continually being generated in a population (what are some of the causes of mutatuions? ) explain

Dna. we have heard that we are a product of our dna. but where is it? how do we "get" our dna? it is passed to us, from our parents, but in what form? several vocabulary words associated with inheritance are used interchangeably and sometimes, incorrectly. let's see if you can clear this up for someone just learning about inheritance and cell structure.