Document 6430210
Transcription
Document 6430210
Lec 5 Reproductive System 1 Lec 9 Objectives List reproduc*ve structures of both a male and female and Describe their func*ons Describe sperm pathway Describe the process of human concep*on. List male and female sex hormones List the major op*ons available for contracep*on Describe the commonly used abor*on methods. Describe fetal development. Describe the three stages of labor and the birth process. Iden.fy the op*ons available to infer*le couples wan*ng children. If contracep*on is one of your reproduc*ve choice for the next three years, name the methods you will likely use and why. 3 The male sex organs 4 © 2010 McGraw-Hill Companies. All Rights Reserved. • Penis Male Sex Organs • The glans • Corpus spongiosum • Urethra • Scrotum • Function (Temperature 93.6 degrees F) • Testes • Epididymis • Vas deferens • Prostate gland • Cowper’s glands • Seminal vesicles • Circumcision 5 © 2010 McGraw-Hill Companies. All Rights Reserved. Functions of Male Reproductive System • Produce sperm cells (sex cells) • Produce male sex hormones • Transfer sperm cells to female 6 Male Sexual Maturation • Normally occurs 2 years later than girls • Begins about 10 or 11 years old • Physical changes – Testicular growth – Penis growth – Pubic hair growth – Voice deepens – Height growth 7 © 2010 McGraw-Hill Companies. All Rights Reserved. 8 Sperm Cells Structure • Head: contain a nucleus and DNA • Midpiece: contain mitochondria • Tail: flagellum for movement 9 Path of Sperm 1. Sperm develop in seminiferous tubules (testes) 2. Epididymis (mature) 3. Ductus deferens 4. Receive secretions from seminal vesicles, prostate gland, and bulbourethral gland 5. Urethra where semen (sperm) exit body 10 Male Sex Hormones Hormone Source Function Gonadotropinreleasing hormone hypothalamus stimulates secretion of LH and FSH LH (luteinizing) anterior pituitary gland stimulates secretion of testosterone FSH (follicle-stimulating) anterior pituitary gland prompts spermatogenesis Testosterone interstitial cells in testes involved in development and maintenance of reproductive organs 11 Female Sex Organs 12 © 2010 McGraw-Hill Companies. All Rights Reserved. Functions of Female Reproductive System • Produce female oocytes (sex cells) • Produce female sex hormones • Receive sperm from males • Develop and nourish embryos 13 The female sex organs 14 © 2010 McGraw-Hill Companies. All Rights Reserved. 15 16 Female Sexual Maturation • Physical changes begins around 8-13 with breast development and rapid body growth between 9 and 15. • The 4 Phases of the Menstrual Cycle – Menses • Days 1-5 – Estrogenic phase • Days 6-13 – Ovulation phase • Day 14 – Progestational phase • Days 15-27 17 © 2010 McGraw-Hill Companies. All Rights Reserved. Menstrual Cycle • What is it? series of changes that occur in sexually mature, nonpregnant females • Menses: time when endometrium is shed from uterus • Average is 28 days and results from cyclical changes that occur in endometrium 18 Figure 19.14 19 Menstrual Problems • Dysmenorrhea – Some symptoms caused from prostaglandins • Premenstrual syndrome (PMS) • Premenstrual dysphoric disorder (PMDD) – Causes – Pharmacological treatment • Lifestyle changes to reduce symptoms – Limit salt intake – Exercise – Don’t use alcohol or tobacco – Eat a nutritious diet – Relax – If systems persist, keep a daily diary 20 © 2010 McGraw-Hill Companies. All Rights Reserved. Female Sex Hormones Hormone Source Function Gonadotropinreleasing hormone hypothalamus stimulates secretion of LH and FSH LH (luteinizing) anterior pituitary gland causes ovulation FSH (follicle-stimulating) anterior pituitary gland signals the follicle in ovaries to being development Estrogen follicles of ovaries affects endometrial lining of uterus, breasts, regulates secretions of LH and FSH Progesterone ovaries affects endometrial lining of uterus, secretions, breasts, affects LH and FSH, secondary sexual characteristic. 21 Hormones and The Reproductive Life Cycle • Hormones – Androgens: Sex hormones • Testes produce testosterone • Ovaries produce estrogen and progesterone – Cortex of the adrenal gland produces androgens in both males and females – Pituitary gland – Hypothalamus 22 © 2010 McGraw-Hill Companies. All Rights Reserved. Fertilization (a) A sperm penetrates the zona pellucida. (b) The sperm nucleus fuses with the egg nucleus at fer.liza.on, producing the zygote. Gametes: - sex cells - sperm in males - oocytes (eggs) in females (c) The second cleavage produces the four-‐cell stage. Surface layer of cells (d) Fluid enters the ball and liCs some cells, forming a cavity. This produces the blastocyst, a ball of cells with a surface layer and an inner cell mass Blastocyst Inner cell mass Endo-‐ metrium (Uterine cavity) (e) Implanta.on begins when the blastocyst aEaches to and invades the endometrium. 23 Fig. 8-‐1, p. 206 Differentiation of the Embryo • Determined by the fertilizing sperm at the time of conception – Conception - combining of 23 pairs of chromosomes • 22 are the same and the 23rd is the sex chromosomes • Egg carries an X sex chromosome • Sperm carries either a X or Y chromosome • XX provides the blueprint to produce a female • XY provides the blueprint to produce a male 24 © 2010 McGraw-Hill Companies. All Rights Reserved. How A Baby Grows • Fertilization: union of sperm and oocyte • Zygote – Fertilized egg • Embryo – Implanted zygote • Amnion – Sac enveloping the embryo • Fetus – 9 weeks • Placenta – Supplies fluids and nutrients – Carries wastes away Placenta Why Is Prenatal Care Important? Age • Risks to the fetus rise when mothers are older than 35. Nutrition • Goal: – 22-27 lb weight gain • Maximum Weight Gain: – 35 lbs Substance Use • Risks of smoking and drinking. Physiological Changes of Pregnancy 27 Three Stages of Labor First Stage • Effacement (thinning) • Dilation (opening up) Second Stage • The baby moves into the birth canal and out of the mother’s body. Third Stage • Expulsion of the placenta. Umbilical cord Uterus Placenta Vagina Cervix Sacrum Birth Uterus Placenta (detaching) Perineum Umbilical cord 29 Sex and Your Body Ch 5 Aging and Human Sexuality • Women: Menopause – Ovaries gradually cease functioning – Decreasing estrogen – Increased risk of disease • Men – Gradual decrease of testosterone • As men and women age, sexual activity can continue to be a source of pleasure and satisfaction 31 © 2010 McGraw-Hill Companies. All Rights Reserved. Sexual Functioning • Sexual stimulation – Comes from both physical and psychological stimuli • Physical stimulation – Through the senses – Erogenous zones • Psychological stimulation – Fantasies – Ideas – Memories of past experience © 2010 McGraw-Hill Companies. All 32 Rights Reserved. – Mood Sexual Response Cycle • Physiological mechanisms – Vasocongestion – Muscular tension • Four phases typically characterize the sexual response cycle: 1. Excitement phase 2. Plateau phase 3. Orgasmic phase • Males (refractory phase) 4. Resolution phase 33 © 2010 McGraw-Hill Companies. All Rights Reserved. Figure 5.5 Stages of the Sexual Response Cycle 34 © 2010 McGraw-Hill Companies. All Rights Reserved. The Development of Sexual Behavior • Gender, sexuality, and the mass media • Childhood sexual behavior – Sexual play • Adolescent sexuality • Adult sexuality • Sexuality in illness and disability 35 © 2010 McGraw-Hill Companies. All Rights Reserved. Varieties of Human Sexual Behavior • Celibacy • Autoeroticism and masturbation – Erotic fantasy • Touching and foreplay • Oral-genital stimulation – Cunnilingus (stimulation of the female genitals) – Fellatio (stimulation of the penis) • Anal intercourse • Sexual intercourse 36 © 2010 McGraw-Hill Companies. All Rights Reserved. Sexual Orientation • Person’s preference in sex partners – Heterosexuality – Homosexuality – Bisexuality • Origins of sexual orientation – Biological and genetic factors – Learning theory – Complex series of biological and psychological interactions 37 © 2010 McGraw-Hill Companies. All Rights Reserved. Sexual Behavior • The development of sexual behavior – Gender roles and gender identity • Gender role is everything you do in your daily life that expresses your maleness or femaleness as defined by society • Gender identity is your personal, inner sense of being male or female – Transsexual – those that feel that their biological sex does not match their gender identity – Transvestites – wearing clothing identified with the other gender – Intersexed –born with ambiguous genitals, neither fully female nor fully male. – Biological and cultural influences © 2010 McGraw-Hill Companies. All 38 Rights Reserved. – Gender-role flexibility Sexual Problems • Common sexual health problems • Biological and psychological conditions affecting women: • Vaginitis – Candida (yeast infection) – Trichomonas • Endometriosis • Pelvic Inflammatory Disease (PID) – 50-75% of PID cases are caused by STDs • Biological and psychological conditions affecting men: • Prostatitis • Testicular cancer – Most common in men in their twenties and © 2010 McGraw-Hill Companies. All thirties 39 Rights Reserved. Sexual Dysfunctions • Common sexual dysfunctions – Male – • erectile dysfunction • premature ejaculation • retarded ejaculation – Women – • orgasmic dysfunction • Treatment 40 – Pharmaceutical – Psychosocial - troubled relationships – Behavioral © 2010 McGraw-Hill Companies. All – Relaxation and massage Rights Reserved. techniques Atypical and Problematic Sexual Behaviors • Conflicting feelings about sexuality • Societies attitude toward sexual explicit material and prostitution • Commercial sex – Pornography – Prostitution – Online porn and cybersex 41 © 2010 McGraw-Hill Companies. All Rights Reserved. Responsible Sexual Behavior • Taking responsibility for the consequences • Open, honest communication about intentions • Agreed-on sexual activities • Sexual privacy • The use of contraceptives • Safer sex • Sober sex 42 © 2010 McGraw-Hill Companies. All Rights Reserved. Protecting Your Reproductive Health Abstain Limit sexual intercourse to “outercourse” Talk about birth control with your partner Know what doesn’t work – and don’t rely on it Talk with a health-care professional Consider long term implications Resist having sex without contraceptive protection Use back-up methods Inform yourself about emergency contraception 43 Sexually Transmitted Diseases (STD) Ch 18 The Major STDs • Also known as sexually transmitted infections (STIs) • Spread of an infection from person to person mainly through sexual activity • STDs that pose a major health threat: 1. 2. 3. 4. 5. 6. 7. HIV/AIDS Hepatitis Syphilis Chlamydia Gonorrhea Herpes Human papillomavirus (HPV) • CDC (2008) estimated 65 million Americans were infected with an STD, and about 19 million Americans become newly infected with an STD each year 45 Table 18.1 Annual new cases of STDs in the United States 46 Table 18.2 Sexually transmitted pathogens and associated diseases 47 HIV Infection and AIDS • Human immunodeficiency virus (HIV) is the virus which causes AIDS (acquired immunodeficiency syndrome) • Leading cause of death in some parts of the world • Approximately 65 million people around the world have been infected with HIV since the epidemic began – Nearly 1% of the world’s population – About 3 million new infections per year • 25% of HIV-infected Americans are unaware of their condition 48 What is HIV Infection? • Chronic disease that progressively damages the body’s immune system – HIV attacks and invades CD4 T-cells, monocytes and macrophages – HIV enters a human cell and converts its own genetic material, RNA, into DNA • People with AIDS are vulnerable to a number of serious opportunistic (secondary) infections • Once initial symptoms resolve, the asymptomatic period may last from 2 to 20 years 49 Transmitting the Virus • HIV lives only within cells and body fluids • Three primary means of transmission: – Specific kinds of sexual contact – Direct contact to infected blood – HIV-infected women to her fetus or to infant during breastfeeding – Not through casual contact 50 Figure 18.1 The general pattern of untreated HIV infection 51 Populations of Special Concern for HIV Infection • Most common means of exposure: – Sexual activity between men – Injection drug use – Heterosexual contact • African American men and women are vastly overrepresented among U.S. people newly diagnosed with AIDS 52 Figure 18.2 Routes of HIV transmission among Americans 53 Symptoms of HIV Infection • Within a few days or weeks, some people will develop flulike symptoms – Specialized test HIV RNA assay • Symptoms take months or years to develop, but as immune system weakens, variety of symptoms develop – Pneumocystis pneumonia (fungal infection) – Kaposi’s sarcoma – Difficult-to-treat yeast infections in women – Tuberculosis 54 Diagnosing HIV Infection • Most common tests check for the presence of antibodies to the virus – HIV antibody test – ELISA (first test) – Western blot or immunoflourescence assay is done to confirm results • If HIV positive, the next step is to determine the disease’s severity to plan appropriate treatment 55 Diagnosing AIDS • HIV-positive and either has developed an infection defined as an AIDS indicator or has a severely damaged immune system • Reporting – All diagnosed cases of HIV or AIDS must be reported to public health authorities • Treatment 56 – No cure – Antiviral drugs – Postexposure prophylaxis (PEP) – Treatments for opportunistic infections – HIV and pregnancy – Treatment challenges Sexually Transmitted Diseases Figure 18.3 The life cycle of HIV: How antiviral drugs work 57 What About a Vaccine? • Vaccines are being tested in humans • Licensed AIDS vaccine is not estimated to be at least a decade away – Some experts concede the possibility that a vaccine may never be developed • How can you protect yourself? – Make careful choices about sexual activity – Don’t share drug needles – Participate in an HIV education program 58 Figure 18.4 What’s risky and what’s not: The approximate relative risk of HIV transmission of various sexual activities 59 Chlamydia • Most prevalent bacterial STD in the U.S. • Can cause sterility in men and women – In women, it can lead to pelvic inflammatory disease and ectopic (tubal) pregancy – In men, chlamydia is the most common cause of epididymitis, and causes half of all cases of urethritis • Symptoms – Usually asymptomatic in women – Vaginal discharge, burning with urination, watery discharge from penis, pain around testicles and in lower abdominals 60 Chlamydia • Diagnosis – Examination of tissue samples or urine • Treatment – Once diagnosed, infected person and partner are given antibiotics 61 Gonorrhea • 350,000 new cases reported to the CDC in 2007 • Bacterial infection • Can cause sterility, arthritis, heart problems, PID, ectopic pregnancy, urethritis, and gonococcal conjunctivitis in infants of infected mothers • Symptoms – Usually asymptomatic in women, though frequent burning during urination, menstrual irregularities, pelvic pain, and discharge may occur – Thick yellow-white discharge, and painful urination in men 62 Gonorrhea • Diagnosis – Microscopic exam of discharge can diagnose infection • Treatment – Oral antibiotics can be taken for treatment • Growing number of drug-resistant strains of gonorrhea is a major concern 63 Pelvic Inflammatory Disease • Leading cause of infertility in young women • Symptoms – Long and painful periods, discharge, spotting, low abdominal pain, fever, chills, nausea, and vomiting • Diagnosis – Diagnosis made on basis of symptoms, physical examination, ultrasound, and laboratory tests • Treatment – Antibiotics and hospitalization are normally required 64 Human Papillomavirus Infection • Most common STD in the U.S. • Causes a variety of human diseases: – Common warts – Genital warts – Genital cancers • Highly contagious • New vaccination for HPV: Gardasil – Protects against four types of HPV virus that account for 90% of genital warts and 70% of cervical cancers – Most effective before the onset of sexual activity 65 Human Papillomavirus Infection • Symptoms – Small bump on the skin or a large, warty growth – Cauliflower-like mass – May cause irritation and bleeding • Diagnosis – Diagnosed based on the appearance of lesions – Often detected during routine PAP tests • Treatment – Treatment focuses on reducing the number and size of warts • Cryosurgery (freezing) • Electrocautery (burning) • Laser surgery 66 Genital Herpes • 1 in 5 adults in the U.S. has genital herpes • Two forms cause genital herpes and oral-labial herpes – HSV 1 (Type 1) • Associated with cold sores and fever blisters • Oral-labial herpes • 50-80% of U.S. adults have antibodies to HSV-1 – HSV 2 (Type 2) • Almost always sexually transmitted • Usually occurs during adolescence and early adulthood • Approximately 22% of adults have antibodies to HSV 2 • Remains in the body for life 67 Genital Herpes • Symptoms – 90% of infected people have no symptoms – First episode causes flulike symptoms and genital lesions – Virus remains alive in an inactive state and an outbreak can occur at any time • Diagnosis – Diagnosed through examination of sores and culturing of fluid taken from sores • Treatment – No cure – Antiviral drugs taken at the beginning of an outbreak can shorten the severity and duration of symptoms 68 Hepatitis B • Inflammation of the liver which can cause serious and permanent damage to the liver • Highly contagious but preventable with vaccine • Transmitted through the exchange of bodily fluids • Symptoms – Flulike symptoms, nausea, vomiting, dark-colored urine, abdominal pain, and jaundice • Diagnosis and treatment – Diagnosed through a blood test – No cure • Prevention 69 Syphilis • Can be effectively treated with antibiotics • Symptoms – Primary phase: 10-90 days after exposure • Characterized by painless ulcers, called chancres – Secondary phase: 3-6 weeks after exposure • Characterized by flulike symptoms and highly contagious skin rash – Late, or tertiary, phase • Damage to organs, dementia, cardiovascular damage, blindness, and death • Diagnosis and treatment – Diagnosed by examination of infected tissues and with blood tests – Treated by antibiotics but damage from late stages of infection can be permanent 70 Other STDs • Trichomoniasis – Most common curable STD among young women – Single-celled organism • Bacterial vaginosis (BV) – Abnormal vaginal discharge caused by unhealthy species of normal vaginal bacteria • Pubic lice and scabies – Contagious parasitic infections 71 What You Can Do • Education • Diagnosis and treatment – Get vaccinated – Be alert for symptoms – Get tested – Inform your partners – Get treated • Prevention – Talk openly about your concerns – Know your potential partner 72