Post-Fertilization Event after Zygote Formation:

After the formation of zygote, a series of events occur which are collectively known as post-fertilization events. These events result in the development of the embryo into a mature organism. Let's discuss the post-fertilization events in detail:

1. Zygote Formation: Zygote formation occurs when the sperm fuses with the ovum to form a single cell called zygote.

2. Cleavage: After formation, the zygote undergoes cell division known as cleavage. During cleavage, the zygote divides repeatedly to form a cluster of cells called the morula.

3. Blastulation: The morula undergoes further division and forms a hollow ball-like structure called a blastula.

4. Gastrulation: The blastula undergoes a process called gastrulation, during which the cell layers are formed that will later develop into different organs and tissues of the body.

5. Organogenesis: After gastrulation, organogenesis takes place. During organogenesis, the different cell layers of the embryo differentiate into specific organs and tissues.

6. Fetal development: Once organogenesis is complete, the developing embryo is referred to as a fetus. During fetal development, the fetus grows in size and matures into a fully-formed organism.

Conclusion:

In conclusion, post-fertilization events are a series of complex processes that occur after the formation of zygote. These events result in the development of the embryo into a mature organism. Understanding these events is crucial in the study of embryology and developmental biology.