Biological Differences Chromosomal Sex Gonadal/Hormonal Sex Genital Sex

KEY CONCEPTS Chromosomal Sex Gonadal Sex Hormonal Sex The Basics: 46 Chromosomes, Two Sex Chromosomes, X’s And Y’s Andosperm, Gynosperm, And “Predicting Sex” The Problematic X Chromosome Sex-Linked Traits Gonadal Sex The Indifferent Gonad Gonadal Development Mullerian Ducts--Ovaries and Wolffian Ducts—Testes Hormonal Sex The Adam Principle and the Eve Principle Testosterone (and MIS) and Estrogen Sex-Limited Characteristics

Each contributes 23 chromosomes for a total of 46 Ovum Sperm Each contributes 23 chromosomes for a total of 46 Always an X An X or a Y

X Chromosome Y Chromosome

XX - Female XY - Male

Each contributes 23 chromosomes for a total of 46 Ovum Sperm X-Gynosperm Y-Andosperm Each contributes 23 chromosomes for a total of 46 Always an X An X or a Y

THE PROBLEMATIC X CHROMOSOME Pathological Sex-Linked Traits XX - Female XY - Male THE PROBLEMATIC X CHROMOSOME Pathological Sex-Linked Traits Hemophilia • Color Blindness • Muscular Dystrophy

KEY CONCEPTS Chromosomal Sex Gonadal Sex Hormonal Sex The Basics: 46 Chromosomes, Two Sex Chromosomes, X’s And Y’s Andosperm, Gynosperm, And “Predicting Sex” The Problematic X Chromosome Sex-Linked Traits Gonadal Sex The Indifferent Gonad Gonadal Development Mullerian Ducts--Ovaries and Wolffian Ducts—Testes Hormonal Sex The Adam Principle and the Eve Principle Testosterone (and MIS) and Estrogen Sex-Limited Characteristics

INDIFFERENT GONAD MALE GONAD FEMALE GONAD Gonads Wolffian Duct Müllerian Duct Testosterone MIS Nothing Happens Adam Principle Eve Principle MALE GONAD FEMALE GONAD

SEXUAL DEVELOPMENT TIMETABLE BY GENDER AGE Kind Of Sex MEN WOMEN 6 weeks Chromosomal XY XX Gonadal Undifferentiated 7-12 weeks Testes Ovaries 12-17 weeks Hormonal Estrogen, Testosterone, and Mullerian Inhibiting Substance Estrogen Genital Mullerian ducts degenerate (MIS). The Wolffian ducts differentiate into epididymis, vas deferens, and ejaculatory duct. Wolffian ducts degenerate (automatically). The Mullerian ducts differentiate into fallopian tubes, uterus, and upper vagina 12-20 weeks Penis and descended testes Outer vagina and clitoris Glans and Genital Tubercle become Glans (head of) penis Clitoris Urethral Fold becomes Shaft of the penis Labia minoria Urogenital Slit becomes Raphe (seam at base of penis) Vaginal orifice Labioscrotal Swelling becomes Scrotum Labia majora SEXUAL DEVELOPMENT TIMETABLE BY GENDER

Concepts/Terms You Should Know Today Sex Gonadal Sex Chromosomal Sex Hormonal Sex Genital Sex Hermaphroditism Transsexualism Gender Identity Identity Salience Gender Roles Stereotype Androgyny Masculine v. Feminine Sexuality Sexual Roles Sexual Orientation Gender Statistical Significance Substantive Significance X/Y Chromosomes Andosperm Gynosperm Fertilization Timing Sex-Linked Traits Sex-Limited Traits Recessive X Hemophilia Color Blindness Indifferent Gonad Testosterone Estrogen Adam and Eve Principles Mullerian Inhibiting Substance (MIS) Wolffian Duct System Mullerian Duct System Genital Tubercle Genital Groove Labioscrotal Swelling