Fertilization in animals occurs in a single way, and represents a fusion of egg and sperm. The contribution of the sperm in the future zygote - is j

Fertilization in animals

Fertilization in animals occurs in a single way, and represents a fusion of egg and sperm. The contribution of the sperm in the future zygote — is just its genetic material (haploid set of chromosomes), contained in the nucleus. At the moment of contact of the sperm with the egg front part of the sperm transforms into a tube through which the sperm releases its contents. In fact, it is only the nucleus with the hereditary material. Immediately after the contact of sperm with the egg, on its surface forms the shell, which does not allow penetrating of other sperm into the egg. Simultaneously, occurs the restructuring of the cytoplasm. Only then hereditary material of the sperm, which fell into the egg, merges with the genetic material of the egg. Thus forms a zygote. Taken from http://worldofschool.org

Place of penetration of the sperm into the egg may eventually determine the location of the organs of the future organism. It is known that the part of amphibian oocyte, which is entered by a sperm, during development converts into the front end of the body.

Categories:
Questions:
  • How does the sperm penetrate the egg?