The document provides an overview of the human reproductive system, including its anatomy, physiology, development and functions. It describes the key structures and roles of the male and female reproductive systems, from gamete production and fertilization to childbirth. Key topics covered include the gonads, hormones, menstrual cycle, sexual reproduction and development from fertilization through the embryonic stages.

1. Essentials of Human Anatomy & Physiology
The Reproductive System
Anatomy & Physiology
Mr. Hildebrandt

2. Reproductive System Functions
• Ensure the continuation
of the human species
• Designed to produce, store
& transport gametes
(sex cells).
• Gonads (sex organs) carry out meiosis
to produce gametes:
• Testis – Male gonads produce sperm
• Ovaries – Female gonads that produce
eggs

3. Reproductive System Development
• Sexual Dimorphism (differentiation)
begins soon after fertilization
• Dependant upon the development of
endocrine & urinary systems
• Puberty marks reproductive maturity
• Gamete production slows when there
is a reduction in sex hormones:
• Males – Andropause
• Females - Menopause

4. Male External Genitalia
• Scrotum: divided sac that maintains testes
at 3°C lower than normal body temperature to
protect sperm viability
• Penis:
• Shaft: contains three
areas of erectile tissue
• Glans penis (enlarged tip)
• Prepuce (foreskin)
• Folded cuff of skin around proximal end
• Often removed by circumcision

5. Male Gamete Production
• Spermatogenesis
(sperm production)
begins in the testis and
takes 64-72 days
• Each lobule of the
testis contains 1-4
seminiferous tubules
• Interstitial cells in testis
produce androgens
such as testosterone

6. Sperm Cell – The male gamete
• The only
human
flagellated cell
• DNA is found
in the head
• Are produced
from puberty
until death

7. Male Reproductive System
• Testis – male gonad
• Epididymis
• Ductus (vas) deferens
• Seminal vesicles
• Prostate gland
• Bulbourethral
(Cowper’s) gland
• Urethra

8. Semen – designed to survive the
female reproductive tract
• Mixture of sperm and accessory gland
secretions
• Advantages of additive secretions:
• Fructose provides energy for sperm cells
• Alkalinity of semen helps neutralize the
acidic environment of vagina
• Semen inhibits bacterial multiplication
• Elements of semen enhance sperm motility

9. Male Reproductive System

10. Female External Genitalia
• Vaginal
orifice
• Vestibule
• Clitoris
• Labia majora
• Labia minora

11. Female Gamete Production
• Oogenesis (egg production) takes place
in the ovaries
• The total supply of eggs
are present at birth
• Ability to release eggs
begins at puberty
• Reproductive ability
ends at menopause
• Oocytes (female gamete) are matured
in developing ovarian follicles

12. Ovarian Follicle Stages
• Primary follicle – contains an immature
oocyte
• Graafian (vesicular) follicle – growing
follicle with a maturing oocyte
• Ovulation – when the egg is mature the
follicle ruptures
• Occurs about every 28
days
• Ruptured follicle transforms
into corpus luteum

13. Female Reproductive System
• Ovaries
• Fallopian
tubes
• Uterus
• Cervix
• Vaginal
canal

14. Female Reproductive System

15. Menstrual (Uterine) Cycle
• Pituitary gland secretes follicle stimulating
hormone (FSH) into bloodstream.
• Ovaries recognize FSH & produce
a follicle (egg & supportive cells).
• Follicle secretes estrogen into
bloodstream.
• Estrogen leads is recognized by:
• Pituitary gland which stops secreting FSH
• Uterus which begins to thicken its lining
• Pituitary gland now secretes lutenizing
hormone (LH) into bloodstream.

16. More of the Menstrual Cycle
• The ovary recognizes LH and releases an
ovum – ovulation.
• Supportive cells left behind in the ovary (now
called the corpus luteum) secrete
progesterone into the bloodstream.
• Progesterone is recognized by:
• Pituitary gland which stops secreting LH
• Uterus which rapidly thickens its lining
• If no fertilization occurs, corpus luteum
breaks down & stops making progesterone
• Without progesterone, the extra uterine lining
is shed - menstruation

17. Hormonal Control of the Ovarian and Uterine
Cycles

18. Sexual Reproduction
• Requires sexual dimorphism
• A certain amount of arousal is necessary
• Copulation is the transfer of sperm to
the female reproductive tract
• Fertilization takes place in the female
fallopian tubes
• Embryo implants in the female uterus
• Embryogenesis is comprised of the
23 Carnegie stages of development

19. Human Fertilization
• The oocyte is viable for 12 to
24 hours after ovulation
• Sperm are viable for 12 to 48
hours after ejaculation
• Sperm cells must make their
way to the uterine tube for
fertilization to be possible
• The membrane of the oocyte
does not permit a second
sperm head to enter

20. Human Fertilization

21. Childbirth (Partition)
• Labor – the series of events that expel
the infant from the uterus
• Initiation of labor:
• Estrogen levels rise
• Uterine contractions begin
• The placenta releases
prostaglandins
• Oxytocin is released by the
pituitary
• These hormones produce
contractions

22. Human Mammary Glands
• Modified sweat glands:
• Alveolar glands – clusters
of milk producing glands
within lobules
• Lactiferous ducts – connect
alveolar glands to nipple
• Present in both sexes, but
only function in females
• Stimulated by sex
hormones (mostly
estrogens) to increase
in size