Skip to main content
Back

Female Reproductive System: Anatomy, Physiology, and Hormonal Regulation

NotesPracticeVideo lessons

Study Guide - Smart Notes

Tailored notes based on your materials, expanded with key definitions, examples, and context.

Reproductive System Overview

General Functions and Features

The reproductive system is unique among organ systems in that it does not function continuously, becoming active only at puberty. Both male and female reproductive organs have specialized roles in sexual reproduction.

  • Gamete Formation: Specialized cells for sexual reproduction are called gametes—sperm in males and ova (eggs) in females.

  • Copulation: Sexual intercourse brings gametes together.

  • Fertilization: Genetic information from gametes combines to form a zygote, the first cell of a new individual.

  • Gestation and Parturition: The system supports fetal development and birth.

Common Features of Male and Female Reproductive Systems

Gonads and Accessory Organs

Both sexes have primary sex organs (gonads) and accessory reproductive organs.

  • Gonads: Testes (male) and ovaries (female) produce:

    • Gametes: Formed by meiosis.

    • Sex hormones: Testosterone (male), estrogens and progesterone (female).

  • Accessory Organs: Ducts, glands, and external genitalia facilitate gamete transport and sexual function.

Hormonal Regulation of Reproduction

Hypothalamic-Pituitary-Gonadal (HPG) Axis

The HPG axis coordinates the production of gametes and sex hormones through a sequence of hormonal signals.

  • GnRH (Gonadotropin-releasing hormone): Released from the hypothalamus, stimulates the anterior pituitary.

  • FSH (Follicle-stimulating hormone) and LH (Luteinizing hormone): Released from the anterior pituitary, act on the gonads.

  • Sex hormones: Testosterone, estrogen, and progesterone exert feedback control.

  • Inhibin: Released from gonads, inhibits FSH release.

Figure 26.1 illustrates the HPG axis: Hypothalamus → GnRH → Anterior Pituitary → FSH/LH → Gonads → Sex hormones/inhibin → Target cells.

Activation at Puberty

Puberty marks the onset of reproductive maturity, driven by changes in hormone sensitivity and secretion.

  • Low sex hormone levels suppress GnRH before puberty.

  • At puberty, hypothalamus becomes less sensitive to inhibition, releasing GnRH in pulses.

  • FSH and LH levels rise, stimulating gonadal hormone production and leading to sexual maturation.

Meiosis: Gamete Formation

Definition and Process

Meiosis is a specialized nuclear division occurring only in gonads, essential for sexual reproduction.

  • Reduces chromosome number by half, preventing doubling in the zygote.

  • Sister chromatids: Identical copies joined at the centromere.

  • Homologous chromosomes: One from each parent.

  • Diploid (2n): Two sets of chromosomes (body cells).

  • Haploid (n): One set of chromosomes (gametes).

Most body cells: 2n = 46 chromosomes (23 pairs). Gametes: n = 23 chromosomes.

  • Meiosis involves two consecutive divisions (Meiosis I and II) after one round of DNA replication.

  • Produces four genetically unique haploid cells.

Stages of Meiosis

  • Meiosis I: Homologous chromosomes separate.

  • Meiosis II: Sister chromatids separate.

Figure 26.2 and 26.3 depict the stages and outcomes of meiosis.

Comparison: Mitosis vs. Meiosis

Mitosis produces two identical diploid cells; meiosis produces four unique haploid cells.

Feature

Mitosis

Meiosis

Number of divisions

One

Two

Synapsis of homologous chromosomes

No

Yes

Daughter cell composition

Identical to parent

Genetically different

Role

Growth, repair

Gamete formation

Female Reproductive Anatomy

Ovaries

The ovaries are paired, almond-shaped organs that produce ova and secrete sex hormones.

  • Held by ovarian ligament (medial), suspensory ligament (lateral), and mesovarium (suspends ovary).

  • Blood supply: ovarian arteries and branch of uterine artery.

  • Covered by tunica albuginea.

  • Regions: Cortex (follicles), Medulla (vessels, nerves).

  • Ovarian follicle: Immature oocyte surrounded by follicle or granulosa cells; ovulation ejects oocyte monthly.

Female Duct System

The duct system transports ova and supports fertilization and fetal development.

  • Uterine tubes (fallopian tubes/oviducts): Infundibulum (fimbriae), ampulla (fertilization site), isthmus.

  • Oocyte movement: Peristalsis and ciliary action.

  • Uterus: Hollow, muscular organ; regions include body, fundus, isthmus, cervix.

  • Vagina: Birth canal, menstrual flow passage, copulation organ.

Clinical Considerations

  • Ectopic pregnancy: Fertilized oocyte develops outside uterus; risk of bleeding.

  • Pelvic inflammatory disease (PID): Infection spread can cause infertility.

Uterine Structure and Support

  • Supported by mesometrium, cardinal ligaments, uterosacral ligaments, round ligaments.

  • Peritoneal pouches: vesicouterine (bladder-uterus), rectouterine (rectum-uterus).

Pearson Logo

Study Prep