What is the term for a fertilized egg?

A fertilized egg is referred to as a zygote. This term specifically describes the cell that results from the fusion of a sperm cell and an ovum (egg) during fertilization. The zygote undergoes a series of divisions and developmental stages before becoming an embryo.

In the biological process, after fertilization occurs, the zygote begins to divide through mitosis. This stage precedes the formation of more complex structures like a blastocyst, which occurs later in embryonic development.

Ovum and sperm are terms that refer to the reproductive cells but do not indicate the fertilized state. An ovum is the female reproductive cell, whereas sperm is the male reproductive cell. Therefore, while they are essential for the formation of a zygote, they do not represent the fertilized stage themselves.

The blastocyst is a later stage of development that occurs after the zygote has divided multiple times and formed a hollow structure filled with fluid. It is the stage that implants into the uterine wall but again, it comes after the zygote stage. Understanding these terms highlights the distinct stages of development that occur following fertilization.