Human Development

• Development - involves the formation of sex cells
• Fertilization - is a stage of development that results in a unicellular diploid zygote
• Growth - is a stage of development characterized by an increase in size of an individual
• Testis = Male reproductive system where sperms are produced
• Ovaries - are female gonads that release the oocytes during ovulation
• Epididymis - where sperms are temporarily stored
• Scrotal sac/ Scrotum - supports the testis and epididymis
• Vas Deferens - where the sperm passes through the testis before it joins the urethra
• Urethra- serves as passageway of both sperm and urine and terminates in the external urinary meatus of the penis
• Seminal Vesicle - secretes fluid that forms part of the semen, secretion gives the semen its alkaline characteristic to counteract the acidity of the vaginal tract and therefore, protect the sperm.
• Prostate Gland - Secretes fluid that also provides alkalinity to the semen; it also contains proteolytic enzymes, citric acid, phosphatases, and lipids.
• Bulbourethral Gland - produces a fluid that lubricates the urethra. Paired glands that produce clear, viscous secretion known as pre-ejaculate that helps to lubricate urethra.
• Semen - is a mixture of sperm and spermatic duct secretions and fluids from accessory gland that contribute most of the semen's volume.
• Sperm - are haploid cells, consisting of a flagellum as a tail, a neck that contains the cells energy-producing mitochondria, and a head that contains the genetic material.
• Clitoris - The homologue of the penis in females.
• Vagina- Main entrance to the female reproductive tract
• Cervix - where the vagina ends; projection of the uterus into the vagina; leads to the uterus
• Uterus - also known as the womb; where the embryo develops; with thick muscular walls; blood vessels; and the endometrial lining.
• Endometrium - innermost lining of the uterus where the embryo implant and develop.
• Fallopian tubes - also known as oviducts; paired tubes that are connected to the uterus an terminate near the ovaries; this is where the fertilization takes place.
• Ovaries - female gonads that release the oocytes during ovulation.
• Fertilization - stage of development that results in a unicellular diploid zygote
• Cleavage - stage of development involving a series of mitotic divisions to produce a multicellular blastula from a unicellular zygote.
• Blastocyst - A human blastula composed of the inner cell mass which becomes the embryo, and the tropo-ectoderm, which becomes placenta.
• Implantation - process where the blastocyst implants itself in the endometrium.
• Implantation - signals the start of pregnancy.
• Gestation - carrying of the embryo inside the female reproductive tract, specifically the uterus
• Gestation - can last up to 9 months in humans.
• Stage of Human Development

  Fertilization - Cleavage - Blastocyst - Implantation - Gestation