Not all species need sperm to fertilize an egg for sexual reproduction. Some species need sperm in order to induce completion of egg nucleus development, but then never use the sperm’s DNA. I describe ...

Sexual reproduction is the production of a new organism from two parents by making use of their sex cells or gametes. In this process male gametes fuses with a female gamete to form a new cell called ...

This produces a new cell called a zygote, which will mature into an embryo. The number of cells increase by mitosis, and as the embryo develops, the cells begin to differentiate (or specialise).