Write the proper sequence of the major events in human reproduction
Answers
☆Fertilisation in human----
Fertilization is the process in which haploid gametes fuse to form a diploid cell called a zygote. To ensure that each zygote has the correct number of chromosomes, only one sperm can fuse with one egg.
☆Stages of human development
1• Zygotic stage: The zygote is formed when the male gamete (sperm) and female gamete (egg) fuse.
2• Blastocyst stage: The single-celled zygote begins to divide into a solid ball of cells. Then, it becomes a hollow ball of cells called a blastocyst, attaching to the lining of the mother's uterus.
3• Embryonic stage: The major internal organs and external features begin to emerge, forming an embryo. In this stage, the heart, brain, and spinal cord become visible. Arms and legs start to develop.
4• Fetal stage: Once the formed features of the embryo begin to grow and develop, the organism is considered a fetus. Differentiation and specialization of structures happens during this time.