Study guide: Female and Male Reproductive Systems

📋 Course Outline

1. Intrauterine and Pubertal Development
2. Androgen, Estrogen, and Sex Traits
3. Male System Functions and Structures
4. Male Glands and Semen
5. Female External Genitalia
6. Female Gonads and Cell Division
7. Fallopian Tubes and Uterus
8. Uterine Layers and Disorders
9. Vagina and Breast Anatomy

📖 1. Intrauterine and Pubertal Development

🔑 Key Concepts & Definitions

• Gonads: the primary sex organs that produce gametes and secrete reproductive hormones

★ Must-know

📌 Testosterone is important for external genital development in both sexes; halted testosterone secretion may produce female-appearing genitalia in a male fetus, whereas excessive maternal testosterone may produce male-appearing or ambiguous genitalia in a female fetus.

• Puberty begins when the hypothalamus synthesizes and releases gonadotropin-releasing hormone, which stimulates the anterior pituitary to release follicle-stimulating hormone and luteinizing hormone.

Further detail

• At 5 weeks of intrauterine development, the mesonephric (Wolffian) system is associated with testes and the paramesonephric (Müllerian) system with ovaries.

💡 Memory Hook

GnRH release → FSH and LH secretion → puberty

📖 2. Androgen, Estrogen, and Sex Traits

📝 Essential Points

• Androgens contribute to:

  • muscular development
  • physical growth
  • gonadal growth
  • axillary and pubic hair
  • voice changes
  • facial hair
  • penile growth
  • increased height
  • spermatogenesis

• Estrogens include estrone, estradiol, and estriol and contribute to development of the uterus, fallopian tubes, and vagina, pelvic widening, breast development, pubic and axillary hair, menstruation, vaginal secretions, and fat distribution.

📌 Female secondary sex characteristics include pelvic widening, breast development, pubic and axillary hair, menstruation, vaginal secretions, and fat distribution, whereas male secondary sex characteristics include increased weight and height, testicular and penile growth, facial, axillary, and pubic hair, voice changes, and spermatogenesis.

💡 Memory Hook

Androgens emphasize male traits; estrogens emphasize female reproductive development

📖 3. Male System Functions and Structures

🔑 Key Concepts & Definitions

• Testes: two ovoid glands containing Leydig cells that produce testosterone and seminiferous tubules that produce spermatozoa
• Epididymis: a comma-shaped, tightly coiled tube that lies along the testis and matures and stores sperm before expelling them into the vas deferens
• Gynecology: the study of the female reproductive organs
• Andrology: the study of the male reproductive organs

★ Must-know

📌 The male reproductive system produces sperm in the testes and releases them into the female reproductive tract; successful fertilization forms an embryo that develops during pregnancy, under hormonal control.

Further detail

• The testes normally descend into the scrotal sac during the 34th to 38th weeks of uterine life; delayed descent can cause cryptorchidism.

💡 Memory Hook

Testis → epididymis → vas deferens → ejaculatory duct → urethra

📖 4. Male Glands and Semen

★ Must-know

• The vas deferens carries sperm from the epididymis through the inguinal canal and over the bladder to the ejaculatory duct by peristaltic contractions.

• Seminal vesicles secrete viscous alkaline fluid containing high levels of sugar, protein, and prostaglandins, which improves sperm motility by creating a more favorable pH.

• The prostate is a chestnut-sized gland below the bladder whose urethral passage secretes thin alkaline fluid that further protects sperm by increasing urethral pH.

• Semen is derived from:

  • the prostate gland at 60%
  • the seminal vesicles at 30%
  • the epididymis at 5%
  • the bulbourethral glands at 5%

Further detail

• The male urethra is a hollow mucous-lined tube about 18 to 20 cm long that carries urine and sperm through the penis to the exterior.

💡 Memory Hook

S-P-B: seminal vesicles, prostate, bulbourethral glands

📖 5. Female External Genitalia

🔑 Key Concepts & Definitions

• Vulva: the collective term for the female external genitalia and means covering

★ Must-know

📌 The labia majora are two lateral adipose tissue folds that protect the external genitalia, whereas the labia minora are two medial hairless connective tissue folds containing Bartholin glands.

• The vestibule is the flattened surface inside the labia where the urethral and vaginal openings arise, and the clitoris is erectile tissue with abundant nerve endings involved in sexual arousal and orgasm.

Further detail

• The mons veneris is a pad of adipose tissue over the symphysis pubis, covered by coarse curly hair and protecting the pubic bone junction from trauma.

📌 The posterior fourchette may tear or be cut by episiotomy during childbirth to enlarge the vaginal opening, whereas an imperforate hymen can block menstrual blood and sexual relations until surgically incised.

💡 Memory Hook

A protective vulvar gateway surrounding the vestibule and vaginal opening

📖 6. Female Gonads and Cell Division

🔑 Key Concepts & Definitions

• Ovaries: two female gonads that contain ova, release mature eggs, produce estrogen and progesterone, and regulate menstrual cycles

★ Must-know

• At birth, each ovary contains about 2 million immature ova formed during 5 months of intrauterine life.

• During meiosis, ova and spermatozoa are reduced to half the usual chromosome number; an ovum contains 22 autosomes and an X chromosome, while a spermatozoon contains 22 autosomes and either an X or Y chromosome.

📌 Fusion of an ovum with an X-carrying sperm produces an XX female, whereas fusion with a Y-carrying sperm produces an XY male.

Further detail

• The number of ova declines from about 2 million in each ovary at birth to 500,000 by age 7, approximately 300,000 by age 22, and none remain by menopause.

💡 Memory Hook

Oocyte formation → meiosis → ovulation → fertilization

📖 7. Fallopian Tubes and Uterus

🔑 Key Concepts & Definitions

• Ampulla: the longest portion of the fallopian tube, measuring about 5 cm, where fertilization usually occurs
• Uterus: a hollow pear-shaped muscular organ posterior to the bladder and anterior to the rectum that receives the ovum, supports implantation and fetal growth, and expels the fetus at maturity

★ Must-know

• The fallopian tube has four parts:
  • interstitial portion
  • isthmus
  • ampulla
  • infundibulum

Further detail

• Fimbriae are small projections on the funnel-shaped infundibulum that guide the ovum into the fallopian tube and help conduct it toward the uterus through peristaltic motion.

• The uterus has three divisions:

  • body or corpus
  • isthmus
  • cervix

💡 Memory Hook

Interstitial portion → isthmus → ampulla → infundibulum

📖 8. Uterine Layers and Disorders

🔑 Key Concepts & Definitions

• Bicornuate Uterus: a horn-shaped uterine malformation caused by impaired fusion of the Müllerian ducts

📝 Essential Points

• The endometrium is the inner mucous layer involved in menstruation and pregnancy support, the myometrium is the middle smooth-muscle layer, and the perimetrium is the outer connective-tissue layer providing support.

• Overstretched pelvic supports can allow the bladder to bulge into the anterior vagina, producing a cystocele, or the rectum to pouch into the vaginal wall, producing a rectocele.

• Anteversion means the uterine fundus is tipped forward, retroversion means the fundus is tipped backward, anteflexion means the body bends sharply forward at the cervix, and retroflexion means the body bends sharply backward.

💡 Memory Hook

Endometrium supports pregnancy; myometrium contracts; perimetrium supports

📖 9. Vagina and Breast Anatomy

🔑 Key Concepts & Definitions

• Vagina: a hollow musculomembranous canal posterior to the bladder and anterior to the rectum that extends from the cervix to the external vulva and functions in intercourse, menstrual discharge, sperm transport, and childbirth

📝 Essential Points

• Döderlein's bacilli are lactose-fermenting bacteria that make the vagina acidic.

• External breast structures include: nipple, areola, Montgomery's tubercle glands, mammary glandular tissue with fat and connective tissue

📊 Synthesis Tables

Male and female secondary sex characteristics

Female	Male
Pelvic widening and breast development	Increased weight and height
Menstruation and vaginal secretions	Voice, penile, and testicular growth
Pubic and axillary hair	Facial, axillary, and pubic hair
Fat distribution	Spermatogenesis

Uterine positional deviations

Condition	Change
Anteversion	Fundus tipped forward
Retroversion	Fundus tipped backward
Anteflexion	Body bent forward at the cervix
Retroflexion	Body bent backward at the cervix