zygote

Examples of zygote in the following topics:

• Prenatal Brain Development

  • Conception occurs when a sperm fertilizes an egg and forms a zygote.
  • A zygote begins as a one-cell structure that is created when a sperm and egg merge.
  • During the first week after conception, the zygote rapidly divides and multiplies, going from a one-cell structure to two cells, then four cells, then eight cells, and so on.
  • Mitosis is a fragile process, and fewer than one-half of all zygotes survive beyond the first two weeks (Hall, 2004).
  • After the zygote divides for about 7–10 days and has 150 cells, it travels down the fallopian tubes and implants itself in the lining of the uterus.

• The Role of Genes in Prenatal Development

  • The developing zygote gets half of its chromosomes from one parent and half from the other parent.
  • For example, as a zygote develops, gene regulation changes some cells into brain cells and others into liver cells.

• Biology of Sexual Behavior

  • The semen and sperm, as a result of sexual intercourse, can fertilize an ovum in the female's body; the fertilized ovum (zygote) develops into a fetus, which is later born as a child.

• Environmental Impacts on Prenatal Development

  • When the zygote attaches to the wall of the uterus, the placenta is formed.

• Lower-Level Structures

  • http://www.anatomyzone.com 3D anatomy tutorial on the basic parts of the brain using the Zygote Body Browser (http://www.zygotebody.com).