PSYB21H3 Chapter Notes - Chapter 2: Twin Study, Paternal Age Effect, Twin
Document Summary
Fertilization: union of sperm and ovum to produce a zygote; also called conception. At birth a female is believed to have about 2 million immature ova in her two ovaries. After being expelled from the ovary, the ovum is swept along through one of the fallopian tubes. In a sexually mature woman ovulation occurs about once every 28 days until menopause by tiny hair cells, called cilia toward the uterus or the womb. Sperm are produced in the testicles or reproductive glands. Mature males produce hundred million a day and are ejaculated in the semen at sexual climax. It is then deposited into the vagina, where the sperm try to swim through the cervix and into the fallopian tube but only a tiny fraction make it that far. Fertilization usually occurs while the ovum is passing through the fallopian tube. If fertilization does not occur any sperm in the woman"s body dies.
