NEET BIOLOGY

Detailed explanation-1: -During fertilization, the sperm and egg unite in one of the fallopian tubes to form a zygote.

Detailed explanation-2: -Inside the uterus, the blastocyst implants in the wall of the uterus, where it develops into an embryo attached to a placenta and surrounded by fluid-filled membranes.

Detailed explanation-3: -The fertilized egg (zygote) divides repeatedly as it moves down the fallopian tube to the uterus. First, the zygote becomes a solid ball of cells. Then it becomes a hollow ball of cells called a blastocyst.

Detailed explanation-4: -Formation of the fertilization membrane An immediate response to fertilization is the raising of a membrane, called a vitelline membrane, from the egg surface. In the beginning the membrane is very thin; soon, however, it thickens, develops a well-organized molecular structure, and is called the fertilization membrane.

Detailed explanation-5: -Fertilization is a complex multi-step process that is complete in 24 hours. The sperm from a male meets an ovum from a female and forms a zygote; this is the point in which pregnancy begins and leads to a 280-day journey for a female. There are two ways to track this process, and they differ by the day counting begins.