BIO2 - Male & Female Reproductive System PDF

BIO2: Male & Female Reproductive Anatomy Human Reproduction Male Reproductive System Purposes: 1. Produce Sperm 2. Deliver the Sperm to the Egg  Male Reproductive System 1. TESTES Comes from the latin word meaning "witness" because only men could serve as witn...

BIO2: Male & Female Reproductive Anatomy Human Reproduction Male Reproductive System Purposes: 1. Produce Sperm 2. Deliver the Sperm to the Egg  Male Reproductive System 1. TESTES Comes from the latin word meaning "witness" because only men could serve as witnesses! Paired organs that develop from gonads within the abdomen of the fetus. They subsequently descend through a canal into scrotal sacs (a pouch of skin) during the last 2 months of fetal development. Cells in testes make the hormone TESTOSTERONE.  Male Reproductive System 2. SCROTUM maintains testes at cooler temperature than the abdominal cavity. This is necessary for producing viable sperm. Sterility, due to too high body temperature, results if testes fail to descend. 3. SEMINIFEROUS TUBULES are coiled tubules packed into lobes of the testes that produce sperm. They contain diploid cells (2n) that go through meiosis to become haploid (n) sperm cells. 250 m long!  Male Reproductive System 4. EPIDIDYMIS above the testes where mature sperm hang out until they are “called upon”. 5. SPERM – THE MALE GAMETE Men can produce up to 2 million to 3,000,000,000 sperm per day!!! The whole process of spermatogenesis takes about 9 or 10 weeks. SPERMATOGENESIS is the development of sperm; it involves meiosis (cell division that reduces the number of chromosomes by half). Once mature, sperm propelled into VAS DEFERENS by muscle contractions. Sperm moves from storage in vas deferens to URETHRA for ejaculation. (tube that transports sperm and urine)  Sperm Sperm is composed of three parts: HEAD, MIDDLE PIECE, and TAIL (FLAGELLA). In the middle piece are numerous MITOCHONDRIA which provide energy for sperm movement. On the tip of the head is the CAP that contains ENZYMES needed to penetrate the outer barriers of the egg. Male Reproductive System 6. PENIS The penis is a cylindrical-shaped organ that hangs in front of the scrotum. Spongy tissue inside the shaft of penis is flaccid (soft) with normal blood flow in the penis. When spongy tissue fills up with blood, this leads to an erection. 7. ERECTION occurs from increased blood flow filling spongy tissue. IMPOTENCE is failure to become erect.  Male Reproductive System 8. SEMEN Semen is a thick, whitish fluid containing SPERM and secretions from 3 other organs. 9. PROSTATE GLAND surrounds the urethra below the bladder; secretes milky alkaline fluid that aids sperm motility and survival (helps to neutralize the acidic environment in the vagina). Prostate gland enlargement is common in older men; constricts urethra and makes urination difficult. (Prostate cancer is the 3rd largest cancer killer of men.)  02 Female Reproductive System  LET’S GET INTO THE NOTES! Open Google Classroom. Female Reproductive System Purposes: 1. Produce egg 2. Allows (one) sperm to penetrate the egg 3. Grow a human! Over the course of ~28 days each month after puberty, the body of a female undergoes a regular cycle of events, known as the menstrual cycle, that accomplishes these goals.  Female Reproductive System - Ovaries 1. OVARIES Are two egg-shaped to each side of the uterus in the pelvic abdominal cavity. The ovaries produce eggs (ova) and the sex hormones ESTROGEN & PROGESTERONE. Each ovary ~ 3 cm x 1 cm Each month, an ovary produces an egg that bursts from the ovary during ovulation. Release of the oocyte (egg) is called OVULATION. (see picture below)  Female Reproductive System - Ovaries Ovaries contain FOLLICLES that contain oocytes (immature eggs). Female is born with up to 2 million follicles; reduced to about 350,000 - 400,000 at puberty; only. ~400 mature at about one egg per month in the reproductive life of an average woman.  Oviduct (Fallopian Tubes) 2. OVIDUCTS (aka Fallopian tubes) are tubes to the uterus. Oviducts sweep up eggs from the ovary and move the egg to the uterus. Oviducts are also the site of fertilization. Sperm meet and fertilize an ovum in the upper oviduct. "Tubular pregnancy" occurs when embryo implants in the oviduct. “Ectopic pregnancy” is any implantation outside the central body of the uterus.  Uterus / Womb 3. UTERUS / WOMB Is a thick-walled muscular, hollow, pear-shaped organ for nurturing the embryo. It lies above and slants forward over the bladder. It can stretch from 5 cm wide to over 30 cm with a growing baby. The lining of the uterus is called the ENDOMETRIUM. It is composed of connective tissue, glands, and blood vessels. It lines the uterus and, if pregnancy occurs, forms the placenta. * Note: PLACENTA is a temporary organ that develops during pregnancy. It is attached to the endometrium. The umbilical cord is attached to the placenta and delivers oxygen and nutrients (and removes wastes) to the growing fetus.  Cervix 4. CERVIX is located at the back of the vaginal canal. The cervix contains an opening to the uterus. A hysterectomy is the name for the surgical removal of the uterus. 5. VAGINA A muscular tube with mucus lining. The vagina serves in intercourse (receives penis during sexual intercourse) and serves as the birth canal during childbirth. The external genitals are collectively known as the vulva. There are two sets of skin folds called labia which make up the VULVA. * NOTE: female urethra carries urine only!