1. Like begets like i.e; every living organism reproduces its own kind. Frog reproduce frogs, rats reproduce rats only.
2. Heredity includes the characters which are transmitted from generation to generation and these characters are fixed for a particular organism.
1. No two individuals (except the identical twins) exhibit exactly similar characters. Differences are found even between the children of same parents. These are called variations.
2. The cause of genetic or hereditary variations in organisms is the sexual reproduction. All organisms would have
been of the same type if there was no sexual reproduction. Plants produced through vegetative reproduction are usually of the same type.