This chapter discusses the biological and psychosocial bases of human sexuality. It covers topics like genetic and gonadal development of sex, puberty, gender identity, male and female reproductive anatomy and functions, the human sexual response pattern, orientations, and healthy relationships. It provides information about sexuality across the lifespan from childhood to aging.

1. Chapter Twelve: Understanding Sexuality

2. Biological Bases of Human Sexuality Genetic basis XX = female XY = male Gonadal basis Structural development Male genital development Female genital development Biological sexuality and the childhood years Puberty Females: Menarche Males

3. Growth and Development of Sexuality

4. Psychosocial Bases of Human Sexuality Psychosocial sexuality: Masculine and feminine aspects of sexuality Gender : Biological basis of sexuality Gender identity: Recognition of one’s gender Gender preference: Emotional and intellectual acceptance of one’s own gender

5. Psychosocial Bases of Human Sexuality Gender adoption: The long process of learning the behavior that is traditional for one’s gender Gender identification: Achievement of a personally satisfying interpretation of one’s masculinity or femininity

6. Male Reproductive System Testes Sperm development Interstitial cell-stimulating hormone Follicle-stimulating hormone Scrotum Ducts Seminal vesicles Prostate gland Cowper’s glands Penis

7. Male Reproductive System

8. Male Reproductive System Age-related hormone changes Male menopause (andropause) Decrease in level of androgens Prostate size increases

9. Female Reproductive System Mons pubis Labia majora and labia minora Clitoris Vestibule Vagina Uterus Fallopian tubes Ovaries

10. Female Reproductive System

11. Menstrual Cycle Menstrual phase 1 / 4 - 1 / 2 cup of blood and tissue is sloughed off during a 5-7 day period Preovulation phase Lasts about a week Release of FSH and LH leading to ovulation around day 14 Post-ovulation phase Build-up of endometrial tissue Role of progesterone

12. Menstrual Cycle

13. Related Conditions Premenstrual syndrome (PMS) Physical and psychological symptoms that recur during the same phase of the menstrual cycle Premenstrual dysphoric disorder (PMDD) Severe form of PMS Fibrocystic breast condition Excessive secretory activity producing swollen, firm, or hardened tender breast tissue Menopause Gradual decline in reproductive system function, usually by late 40s to mid 50s

14. The Human Sexual Response Pattern Excitement stage – arousal stage Plateau stage – leveling off of arousal immediately before climax Orgasmic stage – neuromuscular tension is released Resolution stage – return of the body to a preexcitement stage

15. Sexual Response Pattern

16. Sexual Response Pattern

17. Differences Between Men and Women in the Sexual Response Pattern Men are not multiorgasmic Men reach orgasm quicker during coitus Women are multiorgasmic Women reach orgasm as quickly as men during masturbation

18. Patterns of Sexual Behavior Celibacy Self-imposed avoidance of sexual intimacy Masturbation Self-stimulation of the genitals Fantasy and erotic dreams Shared touching Genital contact

19. Patterns of Sexual Behavior Oral-genital stimulation Fellatio (oral stimulation of a male’s genitalia) Cunnilingus (oral stimulation of a female’s genitalia) Intercourse Penile penetration of vagina Associated with procreation Anal sex Performed by both heterosexual couples and gay men

20. Aging and Sexuality Sexual activity does decline with age but a significant population of older adults remain sexually active Changes in women: Vaginal lubrication decreases Reduction in orgasmic contractions Changes in men: Erection process is prolonged Decrease in contractions at orgasm Ejaculation decreases in force and volume

21. Sexual Orientation Heterosexuality – Sexual attraction to the opposite gender Homosexuality – Sexual attraction to the same gender “ Gay” refers to a male homosexual “ Lesbian” refers to a female homosexual Bisexuality – Sexual attraction toward both genders

22. Bonds Between People Love Emotional attachment of various levels Intimacy Sharing of deep feelings

23. Qualities of Healthy Relationships Partners Feel safe Treat each other with respect Enjoy spending time with each other Trust each other Have open communication Are interested in each other

24. Bonds Between People Communication in relationships Key to all healthy relationships Recognizing unhealthy relationships Excessive jealousy Dishonesty, irresponsibility, lack of patience Drug abuse Ending a relationship Respect and courtesy Keep message clear and simple

25. Relationships and Lifestyles Singlehood Cohabitation Gay and Lesbian Partnerships Same-Sex Marriage Single parenthood Marriage Divorce Half of all marriages end in divorce Unrealistic expectations

26. Chapter Twelve: Understanding Sexuality