Binary fission in Amoeba:

Binary fission is a mode of asexual reproduction in which only one parent is involved. In binary fission the parent body divides into two daughter cells. It is more convenient to say that the parent body changes into the daughter cells.

Budding in Yeast:

In budding, a small outgrowth is formed on the parent body, known as a bud. This bud on favourable conditions germinates and is detached from the parent body to form a new individual. Hence, in budding the whole parent body is not converted to the new individual but just a part of it.

Budding in yeast