Question

How is a zygote formed in humans?

Answer 1

Hint: Humans undergo a sexual mode of reproduction that involves the production of offspring by the fusion of male and female gametes. The newborn via sexual reproduction will be identical to their parents.

Complete answer:
Reproduction is a biological mechanism by which living organisms give birth to their offspring who are biologically similar to their parents, and this biological process permits and assures the continuity of life on the earth. Based on the organism reproduction is of two type’s i.e. asexual and sexual mode of reproduction.

Human reproduction is a form of sexual reproduction that results in human fertilization, and it typically involves sexual intercourse between a man and a woman. Reproduction occurs after the formation of male and female gametes i.e. sperm and ovum known as gametogenesis, which later fertilizes to give rise to an embryo. This complete process of fertilization in humans is known as internal fertilization as it occurs within the body of a female.

In humans the only motile gamete is sperm whereas the female gamete ova is non-motile in nature, hence the male gametes should be transferred into the female’s body for the process of fertilization. After the transfer of gametes and fusion of male and female gametes, fertilization occurs with the formation of a diploid zygote which is also called a fertilized egg formed by the fusion of sperm and ovum or egg. The zygote stage is brief and this stage is followed by cleavage for the stages of embryogenesis which divides mitotically to form two, four, eight, and sixteen celled stages, and these cells are known as blastomeres. This stage occurs in the first week of fertilization and it contains all the genetic information to form a complete individual.

Note: Zygote is the first diploid cell that is formed by the fusion of male and female gametes which results in the formation of the embryo. It serves as a vital link for the continuation of species from the present to the next generation.