Document 20585

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
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•  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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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–  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
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Figure 5.5 Stages of the Sexual Response
Cycle
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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
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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
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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
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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
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–  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
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thirties
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Sexual Dysfunctions
•  Common sexual dysfunctions
–  Male –
•  erectile dysfunction
•  premature ejaculation
•  retarded ejaculation
–  Women –
•  orgasmic dysfunction
•  Treatment
40 –  Pharmaceutical
–  Psychosocial - troubled relationships
–  Behavioral
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–  Relaxation and
massage
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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
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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
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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
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