Formation of gametes in the ovaties is oogenesis (starts before you're born—men doesn't start until puberty). It beings before female is born with the process of meiosis. Primordial germ cells differentiate into oogonia. Oogonia become primary oocytes. Each is surrounded by follicular cells forming a primordial follicle. —with men hormones are fairly steady until puberty to death. For women hormones work as cycles.28
Monday, March 14, 2016Each month after puberty, FSH and LH stimulate the development of the primordial follicles. They are produced but he anterior pituitary. Only one usually reaches maturity. A few start to grow, developing into primary follicles. While in mature follicle, the diploid primary oocyte completes meiosis I producing a haploid secondary oocyte (with the majority of the cytoplasm) and a haploid first polar body. At ovulation the oocyte enters the uterine tube. If sperm are present and fertilization takes place, the secondary oocyte continues into meiosis II. An ovum and a secondary polar body form. The ovum becomes a zygote when it unites with the sperm.—In males we had a primary spermatocyte which divided into secondary but in females the primary oocyte divides into a first polar body. The polar body goes off and degenerates. The secondary oocyte is important it undergoes ovulation. When it does it may or may not be fertilized with a sperm cell. If 29
Monday, March 14, 2016it is fertilized it will turn into an ovum. Primary oocytes are stuck in prophase I because the hormone levels are not high enough to stimulate maturation. Puberty happens and we end up with a 28 day cycle. At the end what we want is a mature follicle. Secondary oocyte is haploid. The secondary oocyte undergoes ovulation. Hormones trigger this. Uterus is mostly muscle and filled with arteries. The myometrium will only contract during labour. The endometrium is built up and shed every 28 days.30
Monday, March 14, 2016The vagina: A fibromuscular canal lined with mucous that extends from the body’s exterior to the cervix.The Female Reproductive CycleGonadotropin-releasing hormone (GnRH): from the hypothalamus controls both the ovarian and uterine cycles. The ovary itself is also going to secrete hormones, progesterone and estrogen. FSH (follicle stimulating hormone): causes initial development the follicles. Estrogen: promotes maintenance of female reproductive growth (secondary sex characteristics) ie. mammary glands and ducts causes increase in protein production and lowers blood pressure. As estrogen goes up the walls of the endometrium will get thicker. Typically if estrogen is high progesterone is low and vice versa. Typically before implantation or period one of the two hormones is high.Relaxin works during labour to relax and create flexibility within the pubic symphysis. Theres a cycle in the ovary and a cycle in the uterus which happen simultaneously.
You've reached the end of your free preview.
Want to read all 38 pages?
- Summer '19
- Anatomy, Nephron, Glomerulus