Normally, the egg after ovulation cannot be observed directly with the naked eye and needs to be viewed under a microscope. The egg is surrounded by many granulosa cells arranged in a radial pattern in the outer layer of the egg cell. The diameter of the egg is usually about 20mm. The ovum after ovulation is called a mature egg, which is surrounded by many granulosa cells that are arranged in a radial pattern in the outer layer of the egg cell, constituting the radial crown of the egg cell. These granulosa cells are arranged in a radial pattern in the outer layer of the oocyte, forming the radial crown of the oocyte. The egg is usually translucent and can survive for 1 to 2 days after ovulation. If it combines with sperm during the survival period, it can develop into a fertilized egg. If it does not combine with a sperm, it liquefies and loses its ability to be fertilized.