Chapter 6 Outline
Development Passes through Distinct Stages
- Fertilization Is the Fusion of One Sperm with One Ovum
- The Conceptus Implants in the Uterine Wall
- During Embryonic Life, the Body Plan and Organ Systems Develop
- Fetal Life Involves Growth and Functional Maturation
Study questions: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11
Genetic Sex Is Determined at Fertilization
- Sex Is Usually Determined by the Presence or Absence of the Y-Linked Gene SRY
- Box 6.1: Biology of Sex: Atypical Development: Chromosomal Anomalies
- SRY and Other Genes Direct the Development of the Gonads
- Box 6.2: Biology of Sex: Atypical Development: Gonadal Intersexuality
Study questions: 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19
Sexual Development Involves Growth or Breakdown of Precursor Structures
- Primordial Germ Cells Migrate into the Developing Gonads
- Male and Female Reproductive Tracts Develop from Different Precursors
- Box 6.3: Biology of Sex: Atypical Development: Androgen Insensitivity Syndrome
- Male and Female External Genitalia Develop from the Same Precursors
- Box 6.4: Biology of Sex: Atypical Development: Congenital Adrenal Hyperplasia
- Box 6.5: Biology of Sex: Atypical Development: 5α-Reductase Deficiency
- Box 6.6: Biology of Sex: Atypical Development: Hypospadias and Micropenis
- The Gonads Descend during Development
Study questions: 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35
Hormones Influence the Sexual Differentiation of the Central Nervous System
- The CNS Contains Sexually Dimorphic Structures
- Sexual Dimorphism Arises as a Consequence of Differing Hormonal Levels during a Sensitive Period
Study questions: 36 | 37 | 38 | 39
Early Hormonal Exposure Influences Later Sexual Behavior
- Experiments on Rodents Show Organizational and Activational Effects of Androgens
- Primates Have Multiple Sensitive Periods
Study questions: 40 | 41 | 42 | 43 | 44
Other Y-Linked Genes Besides SRY Influence Development
Study questions: 45
External Factors Influence Prenatal Sexual Development
- Biological and Social Factors Interact Postnatally
Study questions: 46 | 47 | 48
Puberty Marks Sexual Maturation
- The Pubertal Growth Spurt Occurs Earlier in Girls than in Boys
- Puberty Is Marked by Visible and Invisible Changes in the Body
- What Drives Puberty?
- Box 6.7: Biology of Sex: Atypical Development: Precocious and Delayed Puberty
- The Body May Signal Its Readiness for Puberty to the Brain
- Dietary Changes May Be the Reason Puberty Is Beginning Earlier
Study questions: 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65
Intersexuality Raises Complex Social and Ethical Issues
- Box 6.8: Personal Points of View: What It’s Like to Be Intersexed
Study questions: 66
