Ovum
Updated:An ovum, also known as an egg cell, is the female reproductive cell in humans and other animals. It is one of the largest cells in the human body, typically around 0.1mm in diameter, and is visible to the naked eye. The ovum contains half the genetic material needed to create an offspring and has the potential to develop into a new individual upon fertilization by a sperm cell.
Additional Information
Ova (plural of ovum) are produced in the ovaries through a process called oogenesis. At birth, a female has all her ova in an immature state. During the menstrual cycle, usually one ovum matures and is released from the ovary in a process called ovulation. If the ovum is fertilized by a sperm, it may implant in the uterine wall and develop into an embryo. If fertilization does not occur, the ovum disintegrates and is shed along with the uterine lining during menstruation.
Examples
The ovum is surrounded by the zona pellucida, a glycoprotein membrane that the sperm must penetrate for fertilization to occur.
In in-vitro fertilization (IVF), mature ova are collected from the ovaries and fertilized by sperm in a laboratory setting before being implanted in the uterus.