POWERPOINT LECTURE SLIDE PRESENTATION by ZARA OAKES MS

POWERPOINT® LECTURE SLIDE PRESENTATION by ZARA OAKES, MS, The University of Texas at Austin UNIT 4 26 PART A Reproduction and Development HUMAN PHYSIOLOGY AN INTEGRATED APPROACH DEE UNGLAUB SILVERTHORN Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings FOURTH EDITION

Sex Determination § Dimorphism- physical differences in females and males other and reproductive organs. § Physically distinct- breast, hips, muscle mass, areas of body fat storage, etc. § Gonads produce gametes (eggs and sperm) § Male gonads testes sperm § Female gonads ovaries eggs § Internal and external genitalia – glands and ducts that connect the gonads to the external genitalia Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Sex Determination § Chromosomes – a DNA segment that holds genes. Chromosomes come in pairs called homologous pairs § Autosomes – code for body characteristics but do not determine sex § 22 pairs § Sex Chromosomes -X &Y § men are XY women are XX Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -1

Sex Determination Inheritance of X and Y chromosomes Each parent contributes ½ the genome to an offspring. During sex determineation; mothers always contribute the X chromosome. Father’s have a 50: 50 chance of giving an X or Y Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -2

Sexual Differentiation § Bipotential tissues – undifferentiated tissues the can develop into male or female reproductive structures. § SRY gene – sex-determining region of the Y chromosome that will guides the development of male genitals. § Gonad - the reproductive organ that produces the gamete § Testis or ovary – primary reproductive organ, all other reproductive structures are accessory structures that make fertilization and pregnancy possible. § Wolffian duct- derived from the embryonic kidney, it develops into the vas deference once the testes release Anti-Mullerian hormone. § Mullerian duct - derived from the embryonic uterus, it develops into the fallopian tube while Wolfian duct disappear in the absence of testorone. Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Development of Internal Organs Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin

Sexual Differentiation Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Development of External Genitalia Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin

Gametogenesis § Gamete production occurs in primary sex organs. Begins in utero, stops during childhood, resumes in puberty and continues through adulthood. The process is timed differently in males & females § Meiosis- cell division occurring only in gametes that yields four haploid cells (different from mitosis) § Primary gamete-produced at completion of Meiosis I. The cell is genetically diverse, haploid (no chromosome pairs) and with sister chromatids (copies= 46 total) § Secondary gamete-produced at completion of Meiosis II. The cell is genetically diverse, haploid, and with no sister chromatids (23 total) § Haploid gamete- carries half the genome, matures into a viable cells that participates in fertilization Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Comparing Mitosis and Meiosis Mitosis § Mitosis yields two identical diploid cells. It’s happens in all body cells (somatic) § Meiosis yields four genetically diverse haploid cells. It only happens in sex cells (gametes) Meiosis Parent cell (2 n) Chromosome duplication Meiosis I Parent cell (2 n) Chromosome duplication Tetrad Crossing over Daughter cells 2 n 2 n Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Meiosis II n n n Daughter cells n Visual Summary 8. 3

Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Gametogenisis in the

Spermatogenesis STAGE OF CELL DIVISION Spermatogonium MITOSIS FEMALE 46 (diploid) Spermatogonia Sister chromatids Secondary spermatocyte MEIOSIS DNA replicates but no cell division occurs. 2 sets of 46 chromosomes First meiotic division Primary gamete divides into two secondary gametes. 23 chromosomes duplicated Spermatids Second meiotic division develop into Secondary gamete divides. Sperm 23 chromosomes (haploid) Reproductive adult Primary spermatocyte 46 chromosomes per cell (only two shown here) Embryo Germ cell proliferation Reproductive adult In males meiosis begins in adulthood after puberty, all cells generated by meiosis can develop into sperm. MALE One primary spermatocyte yields 4 sperm. Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -5 (4 of 9)

Maturation of Sperm Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Spermatozoa Structure § Head § Acrosome and nucleus § Midpiece § Centrioles and mitochondria § Tail (flagellum) § Microtubules Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

In females stem cells go through mitosis and creates all the oocytes that could mature into an ovum. Meiosis begins before birth, is arrested, and then resumes after puberty but is not completed until fertilization occurs. Oogenesis Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Gametogenesis & Fertilization STAGE OF CELL DIVISION MALE Spermatogonium FEMALE Oögonium MITOSIS Secondary spermatocyte Spermatids develop into Sperm One primary spermatocyte yields 4 sperm. Reproductive adult Sister chromatids Embryo 46 (diploid) Spermatogonia Primary spermatocyte 46 chromosomes per cell (only two shown here) MEIOSIS DNA replicates but no cell division occurs. Second meiotic division Secondary gamete divides. First polar body Secondary oocyte (egg) (may not occur) Disintegrates Egg released from ovary at ovulation 23 chromosomes (haploid) One primary oocyte yields 1 egg. FERTILIZATION Zygote Cummings Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Primary oocyte Sister chromatids 2 sets of 46 chromosomes First meiotic division Primary gamete divides into two secondary gametes. 23 chromosomes duplicated Oögonia Reproductive adult Embryo Germ cell proliferation Second polar body disintegrates. Unfertilized egg passes out of body. Figure 26 -5 (9 of 9)

Synthesis Pathways of Steroid Hormones § Steroid hormones contain cholesterol, are structurally similar and share production pathways with other steroid hormones § Ovary § Progesterone § Estrogen § Testis § Testosterone Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Regulation of Reproduction by Endocrine System § Both males and females produce the following, the primary target tissues are the gonads. The gonads produce androgens (predominate in males) and estrogens (predominate in females). § Hypothalamus: pulse generator of § Gonadotropin releasing hormone (Gn. RH) § Anterior Pituitary § Lutenizing hormone (LH) § Follicle stimulating hormone (FSH) § Inhibins and activins- influence the secretion of FSH Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

General Pathways General pattern of hormonal control of reproduction § Long-loop: hormone production by gonads alters § Gn. RH Hypothalamus Short-loop negative feedback KEY Stimulus Anterior pituitary Integrating center Gn. RH FSH § LH Efferent pathway Effector Long-loop feedback may be negative or positive es Steroid and peptide hormones ly on Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Gonads (ovaries or testes) al Gn. RH Endocrine cells Tissue response FSH m § Short-loop: feedback from pituitary alters LH Fe § § Internal and environmental stimuli CNS Gamete production Figure 26 -7

Histology of the Testes § Seminiferous tubules contain § Spermatogonia- goes through various stages to become sperm (spermatogonia, spermatocyte, spermatids, & sperm) § Sertoli cells (sustentacular cells)found between spermatogonia, form part of the blood-testes barrier produce inhibin & activin § Interstitial tissue (found outside of seminiferous tubules but within testicles) § Leydig cells- produce testosterone, active in fetus and after puberty Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Regulation of Spermatogenesis § Gn. RH FSH Sertoli cells spermatocyte maturation Hypothalamus § Short and long loops Integrating center Efferent pathway Effector Tissue response Anterior pituitary § Inhibin feedback § FSH, testosterone KEY Gn. RH FSH Inhibin LH Spermatogonium Spermatocyte Testes Second messenger Sertoli cell Cell products Androgen-binding protein (ABP) Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings ABP T

Regulation of Spermatogenesis § Gn. RH Leydig cells testosterone sex characteristics § Inhibin feedback § FSH, testosterone § Short and long loops Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Male Reproductive Structures § Male reproductive structures are designed to create sperm, deliver it internally, and provide it with chemicals to allow it to survive outside the body Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Male Reproductive Structures Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Male Reproductive Structures Accessory glands: produce secretions that in addition to sperm, form semen. 1. Seminal vesicles: secrete a fluid that contains fructose (sugar), nutrients, prostagladins to stimulate the urethra to contract, substances that suppress the immune system against sperm in females, enzymes the enhance sperm mobility, and enzymes that thicken the ejaculate. 2. Prostate gland: release a milky white fluid that enhances sperm mobility & thickens ejaculate. Susceptible to tumors & STDs. 3. Bulbourethral glands: secrete a mucus for lubrication and neutralizes acid in urethra. Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -8 (1 of 2)

Female Reproductive Structures § External genitalia § Vulva § Labia Majora & Minora § Clitoris § Urethral & Vaginal opennings § Passageway § Urethra § Vagina § Hymen § Birth canal Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Female Reproductive Structures The female reproductive system is designed for ova(egg) production, fertilization, fetal development, and fetal delivery. It involves a uterine and ovarian cycle Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Female Reproductive Structures § These structures are supported by the broad ligament. The uterus is not the place of fertilization, thus changes to the lining of the uterus occur in preparation of implantation and then development of the fetus Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Ovaries: Structures § Follicle: primordial, primary, secondary, matured (antrum), ruptured § Oocyte § Follicular cells § Thecal cells § Granulosa cells § Corpus luteum § Corups albicans Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Phases of the Ovarian & Uterine Cycle § Primary hormones § Gn. RH from the hypothalamus § FSH and LH from the anterior pituitary § Estrogen, progesterone, and inhibin from the ovary § Ovarian Cycle: § Follicular phase: Follicle growth in ovary (egg matures) § Ovulation: Ripened follicles and release of oocyte(s) § Luteal phase: Ruptured follicle becomes corpus luteum in preparation for pregnancy § Uterine Cycle: § Menses: No pregnancy, Bleeding from uterus § Proliferative phase: New layer of endometrium in preparation of pregnancy § Secretory phase: Conversion of endometrium to secretory structure Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Hormonal Control of the Menstrual Cycle: Follicular Phase and Ovulation (a) Early to mid-follicular phase (b) Late follicular phase and ovulation Gn. RH Hypothalamus Pituitary FSH Follicle Granulosa cells Thecal cells Androgens Estrogens LH LH FSH Inhibin Thecal cells Androgens High estrogen Small amount of output progesterone LH FSH KEY Ovum Stimulus Integrating center Follicle Inhibin Estrogen Corpus luteum Progesterone Efferent pathway Tissue response Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -14 (2 of 4)

The Menstrual Cycle: Ovarian & Uterine Cycle § FSH stimulates follicular development § Maturation to secondary and tertiary follicle § Granulosa cells produce estrogen § Positive feedback limits more follicles § Negative feedback decreases FSH and LH secretion § LH stimulates thecal cells to produce androgens Phases of the Ovarian Cycle Follicular Phase Gonadotrophic hormone levels FSH LH Ovarian cycle Primary follicle Ovarian hormone levels Theca Estrogen Inhibin Progesterone Uterine cycle Phases of the Uterine Cycle MENSES 36. 7 Basal body temperature (˚C) 36. 4 DAYS Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings 28/0 7 14 21 28/0

The Menstrual Cycle: Ovarian & Uterine Cycle § High levels of estrogen § LH surge and FSH spike § Egg release § High levels of inhibin § Inhibits production of FSH § Decrease new follicle development § Low levels of progesterone § Positive feedback § Gn. RH and LH Phases of the Ovarian Cycle Follicular Phase Gonadotrophic hormone levels Luteal Phase FSH LH Ovarian cycle Primary follicle Ovarian hormone levels Theca Estrogen Antrum Inhibin Progesterone Uterine cycle Phases of the Uterine Cycle PROLIFERATIVE PHASE MENSES 36. 7 Basal body temperature (˚C) 36. 4 DAYS Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings 28/0 7 14 21 28/0

Hormonal Control of the Menstrual Cycle: Early to Mid-Luteal Phase (a) Early to mid-follicular phase (b) Late follicular phase and ovulation Gn. RH (c) Early to mid-luteal phase Gn. RH Hypothalamus Pituitary FSH Granulosa cells Thecal cells Androgens LH Follicle Estrogens LH LH FSH Corpus luteum (from ovulated follicle) Thecal cells secretes Inhibin Androgens High estrogen Small amount of output progesterone Estrogen Progesterone Inhibin LH FSH KEY Ovum Stimulus Integrating center Follicle Inhibin Estrogen Corpus luteum Progesterone Efferent pathway Tissue response Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -14 (3 of 4)

The Menstrual Cycle: Ovarian & Uterine Cycle § Granulosa cells § Form corpus luteum § Secretes progesterone § High levels of progesterone and estrogen maintain endometrium § Inhibin continues to limit new follicular development Phases of the Ovarian Cycle Follicular Phase Gonadotrophic hormone levels Luteal Phase FSH LH Ovarian cycle Primary follicle Ovarian hormone levels Theca Estrogen Antrum Ovulation Corpus luteum formation Inhibin Progesterone Uterine cycle Phases of the Uterine Cycle PROLIFERATIVE PHASE MENSES SECRETORY PHASE 36. 7 Basal body temperature (˚C) 36. 4 DAYS Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings 28/0 7 14 21 28/0

Hormonal Control of the Menstrual Cycle: Late Luteal Phase (a) Early to mid-follicular phase (b) Late follicular phase and ovulation Gn. RH (c) Early to mid-luteal phase (d) Late luteal phase Gn. RH Hypothalamus Pituitary Tonic secretion resumes FSH Granulosa cells Thecal cells Androgens Corpus luteum (from ovulated follicle) Thecal cells FSH LH Follicle Estrogens LH LH FSH LH Corpus luteum dies New follicles begin to develop secretes Inhibin Androgens High estrogen Small amount of output progesterone Estrogen and progesterone Estrogen Progesterone Inhibin LH FSH KEY Ovum Stimulus Integrating center Follicle Inhibin Estrogen Corpus luteum Progesterone Efferent pathway Tissue response Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -14 (4 of 4)

The Menstrual Cycle: Ovarian & Uterine Cycle § Pregnancy § Maintains high levels of progesterone, estrogen, and inhibin § No pregnancy § Decreased levels of progesterone, estrogen, and inhibin § Menses § High levels of FSH and LH § New follicle development Phases of the Ovarian Cycle Follicular Phase Gonadotrophic hormone levels Luteal Phase FSH LH Ovarian cycle Primary follicle Ovarian hormone levels Theca Estrogen Antrum Ovulation Corpus Mature luteum corpus formation luteum Corpus albicans Inhibin Progesterone Uterine cycle Phases of the Uterine Cycle PROLIFERATIVE PHASE MENSES SECRETORY PHASE 36. 7 Basal body temperature (˚C) 36. 4 DAYS Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings 28/0 7 14 21 28/0

Procreation: Sexual Response § Phases of coitus (sexual intercourse or copulation) § Excitement § Plateau § Orgasm § Resolution § Erection reflex § CNS and spinal integration § Emission § Ejaculation § Erectile dysfunction (ED) Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Erection and Ejaculation in Males KEY Stimulus Receptor Afferent pathway Integrating center Efferent pathway Effector Tissue response Parasympathetic stimulated Sympathetic inhibited Penile arterioles vasodilate. Spinal cord Penis Erection Tactile stimuli Mechanoreceptor Sensory neuron Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -15 (5 of 7)

Erection and Ejaculation in Males Thoughts of Sex!! KEY Stimulus Receptor Afferent pathway Erotic stimuli Integrating center Higher brain centers Efferent pathway Effector Tissue response Ascending sensory pathway Parasympathetic stimulated Sympathetic inhibited Penile arterioles vasodilate. Spinal cord Penis Erection Tactile stimuli Mechanoreceptor Sensory neuron Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -15 (6 of 7)

Erection and Ejaculation in Males Thoughts of Sex!! KEY Stimulus Receptor Afferent pathway Erotic stimuli Integrating center Higher brain centers Efferent pathway Effector Tissue response Descending autonomic Ascending sensory pathways pathway Parasympathetic stimulated Sympathetic inhibited Penile arterioles vasodilate. Spinal cord Penis Erection Tactile stimuli Mechanoreceptor Sensory neuron Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26 -15 (7 of 7)

Pregnancy Prevention § Contraceptives § Abstinence-also prevents STDs § Barriers-prevent sperm from entering cervix § Surgical- prevent the entry of gametes § Pills- affect uterine lining and ovulation http: //portal. stii. dost. gov. ph/s ntpost/frames/Octto. Dec 03/gr apix/contraceptives. jpg Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Pregnancy Prevention Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Fertilization § Sperm capacitation § Swimming and attractants § Egg contact § Penetration § Acrosomal reaction § Nuclear fusion § Cortical reaction § Zygote Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Fertilization Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure 26

Fertilization § When fertilization occurs the sperm does not enter the egg but the fusion of the membranes causes the removal of receptors on the egg so no other sperm can fuse. Notice that meiosis II is only completed if the egg is fertilized Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Zygote Development: Ovulation, Fertilization, and Implantation 3 Days 2 -4: Cell division takes place. 2 Day 1: Fertilization 4 Days 4 -5: Blastocyst reaches uterus. Inner cell Zygote Fallopian tube Egg 1 Ovulation Blastocyst Ovary Uterus Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings 5 Days 5 -9: Blastocyst implants. Figure 26 -18, steps 1– 5

Embryonic Development Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Further Embryonic Development § Chorion and amnion § Placenta § Exchange site § Hormones § Human chorionic gonadotropin (h. CG) § Human placental lactogen (h. PL) § Estrogen and progesterone Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

The Placenta Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings Figure

Development of a Fetus Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin

Regulators of Parturition § Labor onset § Stretch stimulus § Oxytocin § Prostaglandins § Positive feedback loop of parturition Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Parturition: Birth Process § Labor § Rhythmic § Uterine contractions § Cervical dilation §

Mammary Development § Modified sweat glands that are active in pregnant females to produce milk for the infant. These first appear as rudimentary structures in both men and women. When females reach puberty estrogen & progesterone cause the ducts grow but the glands do no fully develop. During pregnancy glandular alveoli form and produce milk shortly after childbirth. § Progesterone secreted in pregnancy actives secretion by the glands § High levels of prolactin after delivery stimulate the production of milk Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

Lactation: Milk Secretion § Prolactin-inhibiting hormone (PIH) § Prolactin § Milk production § Suckling § Inhibits PIH § Oxytocin § Let-down reflex Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

STD STATS § Chlamydia- (bacteria) 3 million new cases per year- 75% have no symptoms. Painful frequent urination, discharge, painful sex, sore throat, fever, nausea § Gonorrhea- (bacteria) 700, 000 cases/year 50% have no symptoms or the same simptoms as Chlamydia § Herpes (virus) 1 million new cases/year, 45 million already have it. 1 in 4 pregnant women have herpes HSV-1 (oral sores) HSV-2 genital § HIV- 7, 000 women give birth per year. 20% of infected babies develop AIDS and die by age 4 § HPV- 75% of the reproductive population is infected ( 3 in 4 people) § Syphilis- 32, 000 new cases/year. A pailess sore is followed by a rash, followed by rough “copper penny” spots on the palm and bottom of feet § Trichomoniasis- a bacteria that affects 5 million women/year. Foul smell, green discharge, itching, redness Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings

http: //picasaweb. google. com/mcmumbi/USMLEIIImages/photo#5089143973170425826 Syphillis Gonorrhea Genital Herpes Trichomoniasis Health. cdwriter. com Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings kiesbeter. nl

§ Chlamydia www. medinfo. ufl. edu § HPV –genital warts www. 4 healthyliving. org § HPV- abnormal cervix & penis § ispub. com § www 2. hu-berlin. de § hopkinskimmelcancercenter. org Copyright © 2007 Pearson Education, Inc. , publishing as Benjamin Cummings