1. Human Reproductive System
Produces, stores, nourishes and transports functional gametes (egg and sperm).

2. 1o Reproductive Organs = Gonads
Gonads make gametes (sex cells) and the Sex Hormones.
Ducts, accessory organs and glands assist gametes
Fertilization - union of sperm and egg = zygote.
2o Reproductive Organs = External Genitalia

3. Male Gonads Female Gonads Testes produce sperm and testosterone.
Ovaries produces eggs, estrogen and progesterone.

4. The Sex Chromosomes XX or XY Female Male
22 pairs of autosomal chromosomes +
1 pair of sex chromosomes.
The Sex Chromosomes
XX or XY
Female Male
X chromosome has about 1,100 genes on it.
Y chromosome has about 80 genes on it.

6. Platypus:
Researchers discovered it has 10 sex chromosomes,
some of them linked to mammals and some to birds.

7. Endocrine Regulation of Reproduction
Gonadotropin-releasing hormone (GnRH)
From Hypothalamus, stimulates FSH and LH release.
FSH:
↑ follicular development, ↑ estrogen (females). Required for sperm production (males).
LH (ICSH in men):
Ovulation.
Regulates estrogen and progesterone (females).
↑ Testosterone (males)

8. Phenotypic Sex Apparent anatomical sex of individual
Sexual differentiation
Male
Female
Lack of Androgens
Induced by Androgens
Mostly Testosterone

9. Testosterone +
Mullerian
Inhibiting
Factor
Male

10. 2o Sexual Characteristic
Differences in anatomy and physiology between males and females = sexual dimorphism.
Characteristic
Males
Females
Pattern of hair growth
Voice (pitch)
Muscle mass
Bone growth/density
Sex drive
Distribution of body fat
Aggression

11. Genetic and Phenotypic Sex
If person with XY has testes that fail to
differentiate and secret hormones - Result?
= genetic male, anatomical female
If person with XY has normal testosterone levels but target tissue lacks receptors - Result?
= genetic male, anatomical female
(testicular feminization syndrome)

12. Sex Chromosome Abnormalities
Female
Genotype
Syndrome
Male XX
Normal XY XO
Turner 
XXY
Klinefelter
XXX
Triple-X
XYY

13. Klinefelters’s Syndrome
Person has 47 chromosomes, the extra one is a Y, genotype = XXY
= Male
Reduced fertility, small testicles, enlarged breast
Turner’s Syndrome
Person has 45 chromosomes, the X or Y is missing, genotype = XO
= Female
Usually Infertile, short, immature sex organs at adolescence

14. Triple-X Syndrome XYY Syndrome
Women with 3X chromosomes - genotype is XXX
“Super-females" or “Meta-females”.
Taller, long legs, slender torsos, limited fertility. 
XYY Syndrome
Males with extra Y chromosome - genotype is XYY. 
“Super-males“ often tall, high testosterone levels. 
Usually fertile. 
Both often unaware of chromosomal abnormality

15. Male Reproductive Structures

16. Male Reproductive Structures
1o Reproductive organ: Testes
Held ‘outside’ body in the scrotum.
Dartos muscle wrinkles skin of scrotum.
Cremaster muscle pulls testes closer to body.
Cremaster Reflex.

17. Ductus deferens – starts after tail of epididymis
~ 18 feet long
~ 3 weeks to travel through
- Head
- Body
- Tail
Stores sperm, recycles
damaged ones, site of
maturation of sperm
Ductus deferens – starts after tail of epididymis

18. The Accessory Glands

19. Accessory Organs of the Male
1. Seminal vesicles
2. Prostate gland
All secrete semen
2. Bulbourethral glands
1. Seminal Vesicles
Paired glands - secretes 60% semen volume.
Fibrinogen – converts to fibrin for clotting.
Fructose – a monosacharide for energy.
Prostaglandins – contract female tract.

20. 2. Prostate Gland 3. Bulbourethral Glands
Single gland - secretes 30% semen volume.
Clotting proteins – to cause initial clots.
Fibrolysin – to liquefy clots.
3. Bulbourethral Glands
Paired glands (~5% semen volume).
Alkaline mucus secretion (to neutralize).
Lubricating properties.

21. Semen Typical ejaculation releases 2-5 ml.
Sperm count typically 50 – 100 million per ml.
Sperm count below 20 million per ml, considered “infertile”.
Sperm must be 2-3o F cooler than rest of body, hence kept ‘outside’ in scrotum.

23. The Penis Erectile tissue (3 masses)
Two corpora cavernosa
One corpus spongiosum (surrounds urethra)
Erection – dilation of arterial smooth muscles.
Erectile Dysfunction (ED)?

24. The Female Reproductive System
Ovaries
Uterine tubes
Uterus
Vaginal canal and vagina
External genitalia

25. Female Reproductive System

27. Uterine Wall (Layers) Endometrium - innermost layer
Functional layer, top 1/3 (sheds).
Basal Layer, bottom 2/3 (remains).
Myometrium – muscular (thickest ~90%).
Perimetrium – outermost covering.

29. The Vagina – passage, connecting uterus to external genitalia.
The External Genitalia:
Labia majora – outer (larger)
Labia minora – inner (smaller)
Clitoris – erectile tissue (spongiosum)
(prepuce = hood, foreskin of clitoris)
Lesser and greater vestibular glands.
Mons pubis