True or false?

You began as a single cell

True.

Every living organism begins as a single cell, which then continues to multiply to grow the single cell into an entire organism. For example, humans start off with a single cell called zygote. It is a diploid cell which contains gametes from both parents. Zygote begins to divide rapidly to form embryo and then fetus and finally develops into a full organism. Hence, it all begins with a single cell.