chapter 22 reproductive system

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  • 1. Hole’s Human Anatomy and Physiology Twelfth Edition Shier  Butler  Lewis Chapter 22 Reproductive Systems Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 1
  • 2. 22.1: Introduction • Male and female reproductive systems are connected by a series of organs and glands that produce and nurture sex cells and transport them to sites of fertilization • Male sex cells are sperm • Female sex cells are eggs or oocytes • Sex cells are produced by a special type of division called meiosis • Meiosis includes two successive divisions , called the first (meiosis I) and second (meiosis II) meiotic divisions 2
  • 3. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Second meiotic division First meiotic division (23 chromosomes, each with 2 chromatids) Paired homologous chromosomes (46 chromosomes, each with 2 chromatids) (23 chromosomes, each with 2 chromatids) (23 chromosomes, each chromatid now an independent chromosome) 3
  • 4. First Meiotic Division • Meiosis I separates homologous (the same, gene for gene) pairs • They may not be identical because a gene may have variants • There are four phases in this division • Prophase I • Metaphase I • Anaphase I • Telophase I 4
  • 5. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) (b) (c) 5
  • 6. Second Meiotic Division • Meiosis II begins after telophase I • This division is similar to mitosis • There are four phases in this division: • Prophase II • Metaphase II • Anaphase II • Telophase II • This division completes with each sex cell having one set of genetic instructions, or 23 chromosomes (compared to two sets (46 chromosomes) in other cells) 6
  • 7. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Parent cell Maternal chromatids Paternal chromatids Gene for blood type Gene for eye color Gene for hair color Result of crossing over 7
  • 8. 22.2: Organs of the Male Reproductive System Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ureter Urinary bladder Superior pubic ramus (cut) Ductus (vas) deferens Large intestine Seminal vesicle Ejaculatory duct Prostate gland Urethra Bulbourethral gland Corpus cavernosum Corpus spongiosum Urogenital diaphragm Penis Anus Glans penis Prepuce (a) Epididymis Testis Scrotum 8
  • 9. Testes Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ureter Urinary bladder Ampulla Seminal vesicle Ejaculatory duct Bulbourethral gland Prostate gland Bulb of penis Crus of penis Root of penis Ductus (vas) deferens Epididymis Testis Penis Urethra Glans penis (b) Body of penis 9
  • 10. Descent of the Testes Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Abdominal wall Testis Lower abdominal cavity Rectum Developing penis Symphysis pubis Gubernaculum (a) Peritoneum Testis Vaginal process (cavity) Inguinal canal Gubernaculum (b) Ductus deferens Tunica vaginalis Scrotum (c) Spermatic cord Testis Gubernaculum 10
  • 11. Structure of the Testes Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Epididymis Ductus deferens Basement membrane Rete testis Spermatogenic cells Spermatogonia Seminiferous tubule Plane of section (a) Lumen of seminiferous tubule Tunica albuginea Testis Sperm cells Interstitial cells (cells of Leydig) Basement membrane Seminiferous tubules Interstitial cells (Cells of Leydig) Sperm cells © The McGraw-Hill Companies, Inc./Al Telser, photographer Spermatogonia (b) 11
  • 12. Formation of Sperm Cells Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Secondary spermatocyte Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Second meiotic division Primary spermatocyte First meiotic division Changes in chromosome structure (23 chromosomes, each with 2 chromatids) Spermatozoa (Sperm cells, 23 chromosomes, 1 chromatid per chromosome) Paired homologous chromosomes Lumen of seminiferous tubule Spermatids Sperm cells Nucleus of sustentacular cell (46 chromosomes, each with 2 chromatids) (23 chromosomes, each with 2 chromatids) Spermatid (23 chromosomes, 1 chromatid per chromosome) Meiosis II Secondary spermatocyte (23 chromosomes, 2 chromatids per chromosome) Primary spermatocyte (46 chromosomes, 2 chromatids per chromosome) Meiosis I Tight junction between sustentacular cells (blood-testis barrier) (23 chromosomes, each chromatid now an independent chromosome) Daughter cell in late interphase ( T ype B spermatogonium, 46 chromosomes 2 chromatids per chromosome) Spermatogonium mitosis Daughter cell in late interphase (New type A spermatogonium, 46 chromosomes 2 chromatids per chromosome) Basement membrane 12 Wall of seminiferous tubule Developmental sequence Sustentacular cells
  • 13. Structure of a Sperm Cell Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Flagellum Nucleus Mitochondria Golgi apparatus Excess cytoplasm Excess cytoplasm and most organelles lost Tail Mitochondria Centriole Midpiece Head Acrosome (a) Acrosome Nucleus Head Midpiece (with mitochondria) © Brand X Pictures/CORBIS Tail 13 (b)
  • 14. Male Internal Accessory Organs • The male internal accessory organs include: • Epididymides • Ductus deferentia • Seminal vesicles • Prostate gland • Bulbourethral glands Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ureter Urinary bladder Ampulla Seminal vesicle Ejaculatory duct Bulbourethral gland Bulb of penis Crus of penis Prostate gland Root of penis Ductus (vas) deferens Epididymis Testis Penis Urethra Glans penis Body of penis (b) 14
  • 15. Epididymides Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Tightly coiled tubes • Connected to ducts within the testis • Promote maturation of sperm cells Epithelial cells Nonmotile cilia Sperm cells 15 © Image Source
  • 16. Ductus Deferentia Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Are muscular tubes • About 45 centimeters each • Extends from the epididymis to the ejaculatory duct Lumen Epithelium Smooth muscle (a) Sperm in lumen of ductus deferens Pseudostratified columnar epithelium Smooth muscle 16 (b) © The McGraw-Hill Companies, Inc./Al Telser, photographer
  • 17. Seminal Vesicles • Attached to the vas deferens near base of the urinary bladder • Secrete alkaline fluid • Secrete fructose and prostaglandins • Contents empty into the ejaculatory duct Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ureter Urinary bladder Ampulla Seminal vesicle Ejaculatory duct Bulbourethral gland Prostate gland Bulb of penis Crus of penis Root of penis Ductus (vas) deferens Epididymis Testis Penis Urethra Glans penis Body of penis (b) 17
  • 18. Prostate Gland • Surrounds the proximal portion of the urethra • The ducts of the gland open into the urethra • Secretes a thin, milky, alkaline fluid • Secretion enhances fluid mobility • Composed of tubular glands in connective tissue • Also contains smooth muscle Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Secretory cells of the prostate gland Smooth muscle Lumen of urethra Manfred Kage/Peter Arnold 18
  • 19. Bulbourethral Glands • Inferior to the prostate gland • Secrete mucus-like fluid • Fluid released in response to sexual stimulation Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ureter Urinary bladder Ampulla Seminal vesicle Ejaculatory duct Bulbourethral gland Prostate gland Bulb of penis Crus of penis Root of penis Ductus (vas) deferens Epididymis Testis Penis Urethra Glans penis Body of penis (b) 19
  • 20. Semen • The fluid the urethra conveys to the outside during ejaculation is called semen • Semen consists of: • Sperm cells • Secretions of the seminal vesicles, prostate gland, and bulbourethral glands • It is slightly alkaline • Contains prostaglandins • Contains nutrients • Volume is 2-5 milliliters of semen per ejaculation • Average 120 million sperm cells per milliliter of semen 20
  • 21. Male External Reproductive Organs • Includes the: • Scrotum (and two testes) • Penis Urinary bladder Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Ureter Large intestine Superior pubic ramus (cut) Seminal vesicle Ductus (vas) deferens Ejaculatory duct Prostate gland Urethra Corpus cavernosum Bulbourethral gland Corpus spongiosum Urogenital diaphragm Penis Anus Epididymis Glans penis Prepuce Testis Scrotum (a) 21
  • 22. Scrotum • Pouch of skin and subcutaneous tissue • Dartos muscle – smooth muscle in subcutaneous tissue; contracts to cause wrinkling of the scrotum • Medial septum divides the scrotum into two chambers • Each chamber is lined with a serous membrane • Each chamber houses a testis and epididymis 22
  • 23. Penis • Conveys urine and semen • Specialized to become erect for insertion into the vagina Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Superficial dorsal vein Deep dorsal vein Dorsal nerve Dorsal artery Deep artery Corpora cavernosa Skin Subcutaneous tissue Connective tissue (fascia) External urethral orifice (a) Tunica albuginea Urethra Corpus spongiosum Prepuce Glans penis (b) 23
  • 24. Erection, Orgasm, and Ejaculation • The erection: • Parasympathetic nerve impulses • Blood accumulates in the erectile tissues • The orgasm: • Culmination of sexual stimulation • Accompanied by emission and ejaculation • The ejaculation: • Emission is the movement of semen into the urethra • Ejaculation is the movement of semen out of the urethra • This is largely dependent on sympathetic nerve impulses 24
  • 25. Erection, Orgasm, and Ejaculation Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sexual stimulation Parasympathetic neurons release nitric oxide, causing dilation of small arteries to penis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Culmination of intense sexual stimulation Veins are compressed, reducing blood flow away from penis Blood accumulates in the vascular spaces within erectile tissues of penis Sympathetic impulses contract smooth muscle Peristaltic contractions in testicular ducts, epididymides, ductus deferentia, and ejaculatory ducts Rhythmic contractions in erectile columns of penis Rhythmic contractions in bulbourethral glands, prostate gland, and seminal vesicles Emission—semen moves into urethra Penis swells and becomes erect Ejaculation—semen is forcefully expelled from urethra 25
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  • 27. 22.3: Hormonal Control of Male Reproductive Functions • Hormones secreted by the hypothalamus, the anterior pituitary gland, and the testes control male reproductive functions • Hormones initiate and maintain sperm cell production and oversee the development and maintenance of male sex characteristics 27
  • 28. Hypothalamic and Pituitary Hormones • The hypothalamus controls maturation of sperm cells and development of male secondary sex characteristics • Negative feedback among the hypothalamus, the anterior lobe of the pituitary gland, and the testes controls the concentration of testosterone 28
  • 29. Male Sex Hormones • The male sex hormones are called androgens • Interstitial cells in the testes produce most of them, but small amounts are made in the adrenal cortex • Testosterone is the most important 29
  • 30. Actions of Testosterone • Increased growth of body hair • Sometimes decreased growth of scalp hair • Enlargement of the larynx and thickening of the vocal cords • Thickening of the skin • Increased muscular growth • Thickening and strengthening of the skeletal bones 30
  • 31. Regulation of Male Sex Hormones Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hypothalamus GnRH – + – Pituitary gland FSH Bloodstream Inhibin Androgens stimulate the development of male secondary sex characteristics and maturation of sperm cells Testosterone and other androgens Release into bloodstream + LH stimulates interstitial cells to secrete androgens (primarily testosterone) Androgens prevent oversecretion of LH Inhibin prevents oversecretion of FSH LH FSH stimulates meiosis in primary spermatocytes to form immature sperm cells; FSH stimulates secretion of inhibin by supporting cells Androgens prevent oversecretion of GnRH Stimulation Inhibition + Testes 31
  • 32. 22.4: Organs of the Female Reproductive System Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Uterine tube Ovary Uterus Fimbriae Rectouterine pouch Fornix Cervix Level of section Coccyx Rectum Urinary bladder Inferior gluteal vein and artery Gluteus maximus m. Sciatic nerve Symphysis pubis Vagina Rectum Levator ani m. Clitoris Labium minus Labium majus Uterus Ischium Urethra Femur Ureter Urinary bladder Femoral nerve, artery, and vein Symphysis pubis Anus Vaginal orifice Anterior (b) (a) 32
  • 33. Ovaries Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Suspensory ligament of ovary Fimbriae of uterine tube Uterine tube (retracted) Ovarian ligament Round ligament of uterus Left ovary Uterus Broad ligament 33
  • 34. Ovary Attachments • Several ligaments hold each ovary in position • The largest is called the broad ligament and is attached to the uterine tubes and uterus • The suspensory ligament holds the ovary at the upper end • The ovarian ligament is a rounded, cord-like thickening of the broad ligament 34
  • 35. Ovary Descent • Like the testes in the male fetus, the ovaries develop from masses of tissue posterior to the parietal peritoneum, near the developing kidney • They descend to locations just inferior to the pelvic brim where they remain attached to the lateral pelvic wall 35
  • 36. Ovary Structure • The tissues of an ovary can be divided into an inner medulla and an outer cortex • The ovarian medulla is mostly composed of loose connective tissue and contains many blood vessels, lymphatic vessels, and nerve fibers • The ovarian cortex consists of more compact tissue and has a granular appearance due to tiny masses of cells called ovarian follicles 36
  • 37. Primordial Follicles • During prenatal development of a female, oogonia divide by mitosis to produce more oogonia • The oogonia develop into primary oocytes • Each primary oocyte is closely surrounded by a layer of flattened epithelial cells called follicular cells, forming a primordial follicle 37
  • 38. Oogenesis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • The process of egg cell formation Secondary oocyte Second meiotic division Zygote 46 chromosomes, 23 from sperm cell and 23 from egg cell (each chromatid now an independent chromosome) Fertilization First meiotic division Primary oocyte Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (23 chromosomes, each with 2 chromatids) Sperm cell (23 chromosomes) Sperm nucleus Second polar body degenerating (46 chromosomes, each with 2 chromatids) (b) or (a) First polar body (23 chromosomes, each with 2 chromatids) First polar body degenerating Courtesy of R.J. Blandau Second meiotic division 38 Polar bodies degenerating
  • 39. Follicle Maturation • At puberty, the anterior pituitary gland secretes increased amounts of FSH, and the ovaries enlarge in response • With each reproductive cycle, some of the primordial follicles mature Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Theca externa Theca interna Granulosa cells Fluid-filled antrum Corona radiata Zona pellucida Primordial follicles Secondary oocyte Primary oocyte (a) Maturing follicle (b) b: © The McGraw-Hill Companies, Inc./Al Telser, photographer © The McGraw-Hill Companies, Inc./Al Telser, photographer 39
  • 40. Follicle Maturation • As many as twenty primary follicles may begin maturing at any one time • One dominant follicle usually out-grows the others • Typically only the dominant follicle fully develops and the others degenerate 40
  • 41. Ovulation • As a follicle matures, its primary oocyte undergoes meiosis I, giving rise to a secondary oocyte and a first polar body • The process of ovulation releases these cells from the follicle Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Uterine tube Secondary oocyte Ovary © 2007 Landrum B. Shettles 41
  • 42. Ovulation Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Corpus albicans Corpus luteum Ovulation Time Uterine tube Time Secondary oocyte Primordial follicle Follicular cells Tim e e Ovary Zona pellucida Tim Primary oocyte Corona radiata Ti m Primary follicle e Follicular fluid First polar body 42
  • 43. Female Internal Accessory Organs • The female internal accessory organs include: • Uterine tubes • Uterus • Vagina Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Uterine tube Fimbriae Rectouterine pouch Fornix Cervix Ovary Uterus Rectum Urinary bladder Symphysis pubis Vagina Urethra Clitoris Labium minus Anus Labium majus Vaginal orifice (a) 43
  • 44. Uterine Tubes Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Suspensory ligament with ovarian blood vessels and nerves Uterine tube Ovary Ovarian ligament Body of uterus Infundibulum Round ligament Fimbriae Secondary oocyte Broad ligament Uterine blood vessels Follicle Endometrium Myometrium Perimetrium Ureter Cervix Cervical orifice Vagina 44
  • 45. Uterine Tubes Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cilia Cytoplasm Nucleus Basement membrane Connective tissue layer (a) (b) a: © The McGraw-Hill Companies, Inc./Al Telser, photographer; b: © Mediscan/Visuals Unlimited 45
  • 46. Uterus Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lumen Endometrium Cilia Cytoplasm Nucleus Basement membrane Myometrium Connective tissue layer Perimetrium (a) (b) a: © The McGraw-Hill Companies, Inc./Al Telser, photographer; b: © Mediscan/Visuals Unlimited © McGraw-Hill Higher Education, Inc./Carol D. Jacobson, PhD., Dept. of Veterinary Anatomy, Iowa State University 46
  • 47. Vagina • A fibromuscular tube that conveys uterine secretions, receives the penis during intercourse, and provides an open channel for offspring Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clitoris Mons pubis Urethral orifice Labium majus Vestibule Labium minus Vaginal orifice Opening of vestibular gland Perineum Anus 47
  • 48. Female External Reproductive Organs • The female external reproductive organs surround the openings of the urethra and vagina and is known as the vulva, and include: • Labia majora • Labia minora Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clitoris Mons pubis Urethral orifice Labium majus Vestibule Labium minus Vaginal orifice Opening of vestibular gland Perineum Anus • Clitoris • Vestibular glands 48
  • 49. Labia Majora • Rounded folds of adipose tissue and skin • Enclose and protect the other external reproductive parts Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clitoris Mons pubis Urethral orifice Labium majus Vestibule • Ends form a rounded elevation over the symphysis pubis Labium minus Vaginal orifice Opening of vestibular gland Perineum Anus 49
  • 50. Labia Minora • Flattened, longitudinal folds between the labia majora • Well supplied with blood vessels Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clitoris Mons pubis Urethral orifice Labium majus Vestibule Labium minus Vaginal orifice Opening of vestibular gland Perineum Anus 50
  • 51. Clitoris • Small projection at the anterior end of the vulva Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clitoris Mons pubis • Analogous to the male penis • Composed of two columns of erectile tissue • Root is attached to the sides of the pubic arch Urethral orifice Labium majus Vestibule Labium minus Vaginal orifice Opening of vestibular gland Perineum Anus 51
  • 52. Vestibule • Space between the labia minora that encloses the vaginal and the urethral openings • The vestibular glands secrete mucus into the vestibule during sexual stimulation Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clitoris Mons pubis Urethral orifice Labium majus Vestibule Labium minus Vaginal orifice Opening of vestibular gland Perineum Anus 52
  • 53. Erection, Orgasm, and Ejaculation Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sexual stimulation Arteries in the erectile tissue dilate; vagina expands and elongates Parasympathetic nerve impulses from the sacral portion of the spinal cord Sexual stimulation intensifies Vestibular glands secrete mucus to lubricate Engorged and swollen vagina increases friction from movement of the penis Orgasm-—rhythmic contraction of muscles of the perineum; muscular walls of uterus and uterine tubes contract 53
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  • 55. 22.5: Hormonal Control of Female Reproductive Functions • Hormones secreted by the hypothalamus, the anterior pituitary gland, and the ovaries control development and maintenance of female secondary sex characteristics, maturation of female sex cells, and changes during the monthly reproductive cycle 55
  • 56. Female Sex Hormones Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hypothalamus + GnRH Pituitary gland FSH, LH (gonadotropins) – Estrogens inhibit oversecretion of gonadotropins Breasts develop Accessory reproductive organs enlarge Bloodstream Gonadotropins + Increased vascularization of the skin Estrogens Increased deposition of adipose tissue in breasts, thighs, and buttocks Stimulates endometrium of uterus to thicken Release into bloodstream Ovaries Stimulation Inhibition 56
  • 57. Female Reproductive Cycle 57
  • 58. 58
  • 59. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Plasma hormonal concentration Ovarian activity LH FSH FSH Ovarian events Developing follicle Mature follicle Follicular phase Days 1 Early corpus luteum LH Regressive corpus luteum Ovulation 7 Corpus albicans Luteal phase 14 21 28 Plasma hormonal concentration Uterine activity Estrogens Progesterone Thickness of endometrium Progesterone Days Estrogens 1 3 Menstruation 5 7 9 11 Proliferative phase 13 15 17 19 21 Secretory phase 23 25 27 1 3 Menstruation 59
  • 60. Menopause • Usually occurs in the late 40s or the early 50s • The reproductive cycles stop • The ovaries no longer produce as much estrogens and progesterone as previously • Some female secondary sex characteristics may disappear • It may produce hot flashes and fatigue • Migraine headaches, backaches and fatigue is possible • Hormone therapy may prevent effects on bone tissue 60
  • 61. 22.6: Mammary Glands • The mammary glands are accessory organs of the female reproductive system specialized to secrete milk following pregnancy 61
  • 62. Location of the Glands • Located in the subcutaneous tissue of the anterior thorax within the breasts • Composed of lobes • Estrogens stimulate breast development in females Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Clavicle Rib Adipose tissue Intercostal muscles Alveolar glands Lactiferous duct Pectoralis major m. Areola Nipple Pectoralis minor m. Ampulla Alveolar duct Alveolar duct 62 (a) (b)
  • 63. Structure of the Glands • A mammary gland is composed of fifteen to twenty irregularly shaped lobes • Each lobe contains glands (alveolar glands), drained by alveolar ducts, which drain into a lactiferous duct that leads to the nipple and opens to the outside • Dense strands of connective tissue form suspensory ligaments that support the breast 63
  • 64. Development of the Breasts • The mammary glands of males and females are similar • As puberty is reached, ovarian hormones stimulate development of the glands in females 64
  • 65. 22.7: Birth Control • Birth control is the voluntary regulation of the number of offspring produced and the time they are conceived • This control requires a method of contraception 65
  • 66. 66
  • 67. Coitus Interruptus • The practice of withdrawing the penis from the vagina before ejaculation, preventing entry of sperm cells into the female reproductive tract 67
  • 68. Rhythm Method • Requires abstinence from sexual intercourse two days before and one day after ovulation 68
  • 69. Mechanical Barriers • Mechanical barriers include the use of a: • Condom • Diaphragm • Cervical cap • Spermicidal foams or jellies 69
  • 70. Chemical Barriers • Chemical barriers include: • Spermicides 70
  • 71. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) (b) (c) (d) (e) a,b: © The McGraw-Hill Companies, Inc./Jill Braaten, photographer; c: © Photolink/Getty Images; d: © Don Farrall/Getty Images; e: © The McGraw-Hill Companies, Inc./Jill Braaten, photographer 71
  • 72. Combined Hormone Contraceptives • These deliver estrogen and progesterone to prevent pregnancy • Various methods are used to deliver hormones including: • A flexible chemical ring (Nuvaring) • A plastic patch (Ortho Evra) • The pill orally (Similar to these combined hormones is the “minipill” which contains only progestin) 72
  • 73. Injectable Contraception • An intramuscular injection of Depo-Provera protects against pregnancy for three months by preventing maturation and release of a secondary oocyte 73
  • 74. Intrauterine Devices • An intrauterine device, or IUD, is a small, solid object that a physician places in the uterine cavity • An IUD interferes with implantation of a blastocyst 74
  • 75. Surgical Methods Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cut and ligated uterine tubes Path of egg Path of sperm Ovary Uterus Cut and ligated ductus (vas) deferens Scrotum (a) Cervix Vagina (b) 75
  • 76. 22.8: Sexually Transmitted Diseases • These are silent infections • Most are bacterial and can be cured • Herpes, warts, and AIDS are viral and cannot be cured • Many cause infertility • AIDS causes death • Symptoms of STDs include: • Burning sensation during urination • Pain in the lower abdomen • Fever or swollen glands • Discharge from the vagina or the penis • Pain, itch, or inflammation in the genital or the anal area • Sores, blisters, bumps or rashes • Itchy, runny eyes 76
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