3. Epididymis located on the upper rear of each testes a. Where sperm cells mature b. Maturing of the sperm cells takes about 18 hours

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1 Human Reproduction The Male Reproductive System A. Performs two major functions 1. Produces sperm cells 2. Deposits the sperm cells within the moist reproductive tract of the female B. Parts of the Male reproductive System 1. Testes male gonad a. Where sperms cells are produced b. Scrotum a sack of skin outside the body where the testes are located. The scrotum keeps the testes 1-2 degrees cooler than the rest of the body c. Produces Testosterone the male sex hormone 2. Seminiferous Tubules small coiled tubules that make up each of the testes a. located within the testes resemble a ball of string b. Where immature sperm cells are made the sperm then travel to the epididymis 3. Epididymis located on the upper rear of each testes a. Where sperm cells mature b. Maturing of the sperm cells takes about 18 hours 4. Vas Deferens Also called the sperm Duct a. Tubes that lead from the epididymis to the urethra b. Sperm travel through the lower part of the abdomen c. A vasectomy (ectomy means removal of) is when the Vas Deferens is cut (usually with heat) this is the male equivalent to getting your tubes tied. 5. Urethra Passageway for sperm cells and urine a. Vas Defrens empty into the urethra b. Semen mixture of sperm and other fluids from the prostate, cowper s seminal vesicles c. The reproductive and urinary system in males uses some of the same organs

2 6. Prostate Gland Located below the bladder a. contributes fluid to the semen b. Protatitis inflammation or swelling of the prostate gland Can block the flow of urine from the bladder and be very painful c. Prostate Cancer One of a handful of cancer types that can be cured provided that early detection takes place. 7. Cowper s Gland AKA bulbourethral gland a. either of two small glands b. contributes fluid to the semen 8. Seminal Vesicles a. located between the rectum and bladder b. serves as a temporary storage site for sperm cells 9. Ejaculation a. the process by which semen leaves the body through the urethra b. reflex actions keep the urinary bladder closed preventing urine from mixing with the sperm cells c. can occur with or without an erection 10. Semen a. mixture of sperm and body fluids from cowper s and prostate gland and also the seminal vesicles b. The ph of semen is basic to protect the sperm cells. The vagina is acidic and that acidity kills about half of the sperm cells upon entry into the vagina.

3 Female Reproductive System A. Function of the female reproductive System 1. produce eggs cells 2. produce the hormones estrogen and progesterone 3. site of internal development provides protection of the fetus B. Parts of the Female Reproductive System 1. Ovaries female gonad a. located in the lower portion of the body cavity b. where the female gametes (ova, oocyte and egg cell) are produced c. oocyte are produced in tiny cavities called follicles d. at birth all potential egg cells are present in an immature form in contrast the male is constantly making sperm. e. Hysterectomy removal of the ovaries permanent 2. Follicle cavities found within each ovary a. each contains an immature egg b. ovulation when a follicle ruptures or breaks open and releases at least one egg cell. More than one is possible this occurs about once a month. c. During the females life no more than 500 eggs mature and are released. 3. Oviducts fallopian tubes a. tubes that do not touch the ovary but are close enough for the egg cell to float into it. b. Leads to the uterus c. Tubal ligation (having your tubes tied) is literally having these tubes tied into a knot. Can be reversed depending on the procedure. d. Site of fertilization by the sperm cell. e. Tubal pregnancy when the fertilized egg stays in the oviduct instead of moving down into the uterus. Can be dangerous for the mother and often times the fetus is aborted with medication.

4 4. Uterus Pear shaped organ a. thick walled to accommodate a fetus and amniotic fluid c. the fertilized egg cell implants itself in the wall of the uterus and finishes development d. Placenta and umbilical cord form where the egg cell implants itself. 5. Cervix narrow neck of the uterus a. mucus plug keeps amniotic fluid from escaping. b. Dilates (opens measured in centimeters) when labor starts c. This is when the water breaks 6. Vagina birth canal a. leads to the outside of the body b. the passageway the baby takes when born (except in the case of a c-section) c. urinary and reproductive tract of the female never meet C. The Menstrual Cycle Facts 1. Begins at puberty (anywhere from ages but every woman is different) 2. Each cycle lasts about 28 days and there are 4 stages to each cycle. 3. Cycle stops during pregnancy and/or illness or stress 4. Permanently stops at menopause (45-50 years old) D. Stages of the Menstrual Cycle 1. Follicle Stage a. involves the maturing of the egg w/in the follicle due to the hormone called FSH or follicle stimulating hormone. b. The hormone estrogen is also released c. Estrogen makes the uterine lining ready for possible pregnancy. d. Lasts about days. 2. Ovulation a. FSH decreases and lutenizing hormone (LH) begins b. Follicle breaks and releases a mature egg this occurs mid cycle around the 14 th day. c. Lasts 1-2 days

5 3. Corpus Luteum Stage a. broken follicle is covered with cells and forms a yellow mass called the corpus lutea b. Progesterone AKA the hormone of pregnancy is secreted or released c. Progesterone brings about more growth in the wall of the uterus. Also temporarily stops the development and maturing of from forming. d. Lasts about days 4. Menstruation fourth and last stage a. occurs only if fertilization and pregnancy does not b. commonly known as getting your period c. LH and progesterone levels decreases and the corpus lutea is shed d. Thickening wall of the uterus breaks down e. Extra layers of the lining, the unfertilized egg cell and blood pass out of the vagina AKA menstruation 5. Fertilization Could also be the fourth stage if sperm cell fertilizes the egg cell a. the fusion of the sperm and egg cell into one cell w/ 46 chromosomes b. Only one sperm cell fertilizes the egg even though about 300 million are released at any one time. c. If fertilization occurs the fourth stage will not occur until after birth d. a fertilization membrane covers the egg once fertilized preventing other sperm form entering 6. Pregnancy A lot is known about pregnancy and after 100 million years of evolution we re still finding out new things such as prevention measures etc.. the bottom line is success rates for humans are much higher than they ever have been

6 7. Development a. After the fertilized egg cell imbeds itself in the wall of the uterus it actually attaches to it and the placenta starts to develop. b. The placenta and the umbilical cord that comes from it are the connection between the fetus and mother. Oxygen, carbon dioxide and nutrients are diffused back and forth. c. The blood of the mother and fetus never mix!! d. Amniotic fluid protects the child from any shock, bumps that they might get during the pregnancy. e. All humans start out female until testosterone is added for the males. 8. Cellular Development three processes a. Cleavage occurs in the oviduct when the zygote undergoes mitosis. b. Blastula the embryo is sphere-shaped and is only one cell thick c. Gastrula 2 layers the embryo is several hundred cells

7 Multiple births Fraternal twins this is when two eggs cells are released at the same time and fertilized by two different sperm cells they may or may not contain similar characteristics Identical twins (paternal) this is when a single fertilized egg is split into two fertilized egg cells which then forms two identical embryos. This can happen randomly and/or appears to be a trait (having twins) passed down from generation to generation. Adolescence: There are four major stages of life: Infancy, childhood, adolescence and adulthood. There are three major changes that occur during the stage known as adolescence. Adolescence is roughly defined as the second decade of life because it does overlap child hood and adult hood The three changes are biological changes, cognitive changes and social changes Let s start off with biological changes: Puberty the physical growth from a child to a sexually mature person usually defines adolescence 1. Development of primary and secondary sex Characteristics 2. Changes in respiratory and circulatory systems allowing for more endurance. 3. Hormones such as testosterone, estrogen and growth hormone and the 1 st period for women 4. Concerns changes in height, weight, fat distribution

8 Some Social Changes also occur Also concerns about whether or not these changes are consistent with your identity to a particular gender i.e. do you look like a female? Why are these changes so important? Adolescents become more health conscious, more aware of personal hygiene, more self conscious Lastly are cognitive or thinking changes AD are now capable of attacking problems so once they accepted things that their parents said without question and now AD question their parents which makes them better arguers as opposed to being more argumentative AD think in more hypothetical terms which allows one to debate an issue and can see the consequences of their actions Imaginary audience AD become very egocentric in that they feel they are the center of attention Personal fable the belief that what you are experiencing is unique to your situation when it turns out just about every adolescent is going through the same thing.

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