Lets talk about SEEEXXX!! ( Ch. 46 Animal Reproduction)

1. Lets talk about SEEEXXX!!( Ch. 46 Animal Reproduction) + Warning: Some graphic images…viewer discretion advised • By: Raveena Patel • Daniel Kim • Mariko Kobayashi • Period 2

2. Before we begin, lets see how much you remember from Mr. Cannon’s Health class???

3. Female Reproductive Systems and Organs

5. Different types of sexual reproduction • Asexual: “ without sex” creation of new individuals whose genes all come from one parent without the fusion of egg and sperm • Sexual: fusion of egg and sperm • Female gamete: egg ( ovum) • Male gamete: sperm

6. Asexual Reproduction • Fission: Separation of a parent into two or more individuals of approximately equal size • Budding: New individuals arise from outgrowths of existing ones. ( ex. Cnidarians ) • Fragmentation: The breaking of the body into several pieces of • Regeneration: The regrowth of lost body parts ( Note: fragmentation must be accompanied by regeneration)

7. Reproductive Cycles and Patterns • Parthenogenesis: process in which an egg develops without being fertilized • Hermaphroditism: each organism has both male and female reproductive systems • Sequential hermaphroditism: a species reverses its sex during its lifetime. ( ex. Sex reversal is commonly associated with age and size)

8. Fertilization • Fertilization: the union of sperm and egg….a very important part of sexual reproduction • External Fertilization: eggs are released by a female into a wet environment, where they can be fertilized by a male. • Internal Fertilization: sperm is deposited in or near the female reproductive tract and fertilization occurs within the tract. • Pheromones: a chemical signal released by one organism that influence the physiology and/or behavior of other individuals of the same species

10. Female Reproductive Anatomy • Ovaries: Female gonads • Ovulation: the release of egg from ovaries. In humans, an ovarian follicle releases an egg during each uterine( menstrual) cycle • Follicle: a microscopic structure in the ovary that contains the developing ovum and secretes estrogen • Oviduct: A tube passing from the ovary to the vagina in invertebrates or to the uterus in vertebrates. • Uterus: thick muscular organ “aka the WOMB” expands during pregnancy

11. Female Reproductive Anatomy cont.… • Endometrium: inner lining of the uterus • Cervix: the neck of the uterus, which opens to the vagina • Vagina: a thin-walled chamber that is repository for sperm during copulation and that serves s the birth canal through which baby is born. • Vulva: External female genitalia • Hymen: a thin membrane that partly overs the vaginal opening in the human female • Vestibule: Vaginal opening and the separate urethral opening, bordered by a pair of slender skin folds. • Labia Minora: thick fatty ridges • Labia Majora: encloses and protects the labia minora and vestibule

12. Guess what even more female reproductive anatomy cont… • Clitoris: an organ in the female that engorges with blood and becomes erect during sexual arousal • Mammary glands: exocrine glands that secrete milk to nourish the young. ( present in both sexes…but normally in women)

14. Male Reproductive Anatomy • Males external reproductive organs are the scrotum and penis • Testes: male gonads, consist of many tubes surrounded by several layers of connective tissue • Seminferous tubules: tubes where sperm form • Scrotum: a pouch of skin outside the abdomen that houses a testis; functions in cooling sperm, therefore keeping them viable • Ducts: • Epididymis: a coiled tubule located adjacent to the testes where sperm are stored ( Cool fact: takes about 20 days for sperm to pass through 6 m long epididymis of a human male) • Ejaculation: the sperm is propelled from the epididymis, then leaves the urethra ( the tube that drains both the excretory system and the reproductive system. )

15. And even more Male Reproductive anatomy cont… • Glands: • 3 sets of accessory glands that add secretion to the semen ( the fluid that is ejaculated) • Seminal Vesicles: a gland in males that secretes a fluid component of semen that lubricates and nourishes sperm. • Prostate gland: a gland in human males that secretes an acid-neutralizing component of semen. • Bulbourethral gland: glands near the base of the penis in the human male that lubricates and neutralizes acids in the urethra during sexual arousal • Fast Fact: A man usually ejaculates 2-5 mL of semen, and each milliliter may contain 50-130 million sperm!!! WOW!!!

16. Just when you thought we were done……Curve ball!! Even more Male reproductive anatomy • Penis: human penis is composed of three cylinders of spongy erectile tissue derived form modified • Baculum: A bone that is contained in, and helps stiffen the penis. • Erection: essential to insertion of the penis into the vagina

18. Hormone regulation • How exactly are gametes produced in the mammalian body? • Gametogenesis: based on meiosis, the finer details differ in females and males. • Oogenesis: the development of mature ova ( egg cells) • Spermatogenesis: the production of mature sperm cells

19. Reproductive cycles of females • Males produce sperm continuously, while females release only one egg or a few eggs at a specific time during each cycle. • Menstrual cycles: the nonpregnant endometrium is shed as a bloody discharge through the cervix into the vagina • Estrous cycles: the nonpregnant endometrium is reabsorbed rather than shed, and sexual response occurs only during mid-cycle at estrus( period of sexual activity) • Ovarian cycle: the cyclic recurrence of the follicular phase, ovulation, and the luteal phase in the mammalian ovary, regulated by hormones • Menopause: when middle aged women go crazy. After about 450 cycles human females go through “the change”, the cessation of ovulation and menstruation. ( age 46-54)

20. Hormonal control of the Male reproductive system • Androgens are steroid hormones produced mainly by the Leydig cells of the testes • Testosterone and other androgens are directly responsible for the primary and secondary sex characteristics of the male • Primary: Associated with the reproductive system; development of external reproductive structures, and sperm production. • Secondary: Features not directly related to the reproductive system, instead it has to deal with deepening of the voice, distribution of facial and pubic hair, and muscle growth.

21. BABIES ARE NOT PARASITES! • Why doesn’t the mom reject the embryo as a foreign body? • the trophoblast prevents the mother’s immune system from doing this by releasing signal molecules with immunosuppressive effects • The trophoblast and placenta secrete an enzyme suppliers of tryptophan • Absence of antigens+hormone secretion=synthesis of death activator memb. Protein(FasL) • Activated T cells contain a complementary FasL and will bind with the other one • T cells self destruct by apoptosis

22. 2 BABIES!!!! That will be a lot of diapers….

24. BIRTH (PARTURITION)! AND BABIES! • Conception- EGG+ SPERM being fertilized, cleavage starts to occur with the zygote until a blastocyst forms which implants into the endometrium which secretes human chorionic gonadotropin ( HCG) – one of the hormones that controls the moms reproductive system • 3 trimesters –each one is 3 months • First- most radical change for the mom and the embryo- which is in then endometrium receives nutrients from it trophoblast mingles with then endometrium an grows outwards and helps form the placenta, organogenesis occurs which is the formation of organs , • Second- the fetus is really active, HCG declines so hormonal levels stabilize, placenta produces progesterone, also when the pregnancy becomes noticeable • Third- this is when the FETUS IS HUMONGOUS, weighs the most, less activity because it’s too dang big, organs become displaced in the mom which causes back pains and frequent urination • We don’t know exactly causes birth, but one way is estrogen levels increase which causes more production of oxycotin which stimulates the placenta to secrete prostaglandins which causes contractions • 3 stages of labors: • 1. dilation of cervix • 2. expulsion of the infant – continues strong contractions force the fetus down and out of the uterus and vagina umbical cord is clamped and cut at this time • 3. delivery of the placenta

26. LACTATION • After birth, decreased levels of progesterone allows anterior pituitary to secrete prolactin to stimulate milk production • Release of milk controlled by oxytocin

27. Contraceptives, Lets practice safe sex guys! • Rhythm/ natural family planning- perform sexual intercourse when the egg is not in the oviduct, 20% of the time it doesn’t work • Coitus interrupts- removal of the penis from the vagina before ejaculation, HIGHLY UNRELIABLE • Barrier method- chance of getting pregnant is less than 10 % - male condoms is a thin latex rubber that fits over the penis to collect the semen - female condoms- diaphragm which is dome shaped rubber cap fitted into the upper portion of the vagina before intercourse - used with spermicidal • Most effective- birth control, abstinence, willpower -synthetic estrogen and progestin for the birth control, negative feedback loop which prevents the release of GnRH by the hypothalamus - prevention of Fsh being released by the pituitary gland = prevention of follicles developing -prevention of LH being released by the pituitary gland= prevention of ovulation -minipill which only contains progestin, builds up the mucus around the uterus to prevent sperm from entering and makes changes in the endometrium which interferes implantation- if fertilization occurs- MANY RISKS WITH THESE PILLS IF TAKEN TOO MANY TIMES • Tubal ligation= GETTING YOUR TUBES TIED, ligating a section of the oviducts to prevent eggs from traveling into the uterus • Vasectomy which in men is cutting if each vas deferens to prevent sperm from entering the urethra • SHOULD BE CONSIDERERD PERMANENT – DIFFUCULT TO REVERSE SO MAKE SURE THAT’S WHAT YOU WANT • Abortion- termination of a pregnancy in progress

29. Lets see if you guys paid attention to our presentation! 1. Which structure is incorrectly paired with its function? a. gonads-produce gametes b. spermatheca- stores sperm in male honeybees c. cloaca- serves as the common opening for the reproductive, excretory, and digestive systems d. baculum-stiffens the penis in some mammals e. endometrium- forms the maternal part of the placenta 2. A difference between estrous and menstrual cycles is that a. Nonmammalian vertebrates have estrous cycles, whereas mammals have menstrual cycles. b. The endometrial lining is shed in menstrual cycles but reabsorbed in estrous cycles. c. Estrous cycles occur more often than menstrual cycles d. Estrous cycles are not controlled by hormones e. Ovulation occurs before the endometrium thickens in estrous cycles. 3. In sequential hermaphroditism, a. Some individuals may change from male to female b. Individuals fertilize themselves c. Males rather than females release pheromones d. Diploid ova are produced e. The adult gonads are undifferentiated. 4. Fertilization of human eggs most often takes place in the a. Vagina b. Ovary c. Uterus d. Oviduct e. Vas deferens 5. In male mammals, excretory and reproductive systems share a. The testes b. The urethra c. The ureter d. The vas deferens e. The prostrate

30. The End

31. This song is our theme song, it will be played in the background while we show our interactive ways to remember some things about sexual reproduction. • http://www.youtube.com/watch?v=MT0E72qnjro