AnaPhy

2. REPRODUCTIVE SYSTEM
 The reproductive system is a collection of internal and external organs — in both males
and females — that work together for the purpose of procreating.
 Due to its vital role in the survival of the species, many scientists feel that the reproductive
system is among the most important systems in the entire body.
 Of the body’s major systems, the reproductive system is the one that differs most between
sexes, and the only system that does not function until puberty.

3. REPRODUCTIVE SYSTEM
• Overall function is to produce
offspring
• Testes produce sperm and male
sex hormones
• Ovaries produce eggs and female
sex hormones
• Mammary glands produce milk

4. MALE REPRODUCTIVE SYSTEM
External Genitalia
Include the scrotum and the penis
A. Scrotum
 is a divided sac of skin that hangs outside the abdominal cavity.
 is responsible for the support of the testes and it regulates the temperature of the
sperm.
 is a rugated, muscular, skin-covered pouch over the perineum.
 To promote the production and viability of the sperm, the scrotum contracts
towards the body during a very cold weather and relaxes away from the body
during a hot weather.

6. MALE REPRODUCTIVE SYSTEM
External Genitalia
B. Penis
 The penis has three parts: two are called the corpus cavernosa, and the other is
the corpus spongiosum.
 These erectile tissues also contain the urethra, making the penis an outlet for
both urinary and reproductive functions.
 The skin covered penis consists of a shaft
 The glans, a sensitive, bulging ridge of tissue, is located at the distal part of the
penis.
 The prepuce (foreskin), which is a retractable casing of skin, protects the glans at
birth. It is also the part that is surgically removed during circumcision.

9. MALE REPRODUCTIVE SYSTEM
External Genitalia
B. Penis
 Erection of the penis is stimulated by the parasympathetic
nerve innervations, and the blood supply for the penis is
from the penile artery.
 Internally, a spongy urethra is surrounded by 3 elongated
areas of erectile tissue
 Erectile Tissue - a spongy tissue that fills with blood during
sexual excitement causing the penis to enlarge and
become rigid

11. MALE REPRODUCTIVE SYSTEM
Testes (Male Gonads)
 Have both exocrine (sperm-producing) function and an endocrine (testosterone
producing) function.
 Each olive-sized testis is approximately 4cm long and 2.5cm wide.
 Several lobules are contained in each testis, which also contains Leydig’s cells
that produce testosterone and seminiferous tubules that produce spermatozoa.
 In most men, one testis is slightly lower than the other to prevent trauma and
easily sit or do any muscular activity.
Internal Structure

12. Testes (Male Gonads)

14. MALE REPRODUCTIVE SYSTEM
Epididymis
The first part of the male duct system
comma-shaped coiled tube that provides a temporary storage site for
immature sperm from the testis
has a length of approximately 20 feet long.
The sperm takes an estimated 12 to 20 days of travel along the epididymis,
and a total of 64 days to reach maturity.

15. Epididymis

16. MALE REPRODUCTIVE SYSTEM
Vas (Ductus) Deferens
is enclosed in a connective tissue sheath called the spermatic cord.
 is a hollow tube that is protected by a thick fibrous coating and surrounded
by arteries and veins.
The function of the vas deferens is to carry the sperm from their storage
sites, the epididymis and distal part of the ductus deferens, into the
urethra.

17. Vas Deferens

18. Vasectomy

19. MALE REPRODUCTIVE SYSTEM
Accessory Glands
A. Seminal Vesicles
 Located at the base of the bladder, produce about 60% of the fluid volume of the
semen.
 Their thick, yellowish secretion is rich in sugar (fructose), vitamin C,
prostaglandins, and other substances which nourish and activate the sperm.
 The duct of each seminal vesicle joins the ductus deferens on the same side to
form the ejaculatory duct.

21. MALE REPRODUCTIVE SYSTEM
Accessory Glands
B. Prostate Gland
This is a chestnut-sized gland which encloses the upper part of the urethra
below the bladder.
It secretes a thin, alkaline fluid that adds protection to the sperm from
being immobilized by the low pH level of the urethra.
During ejaculation, it enters the urethra through several small ducts.

22. MALE REPRODUCTIVE SYSTEM
Accessory Glands
C. Bulbourethral Glands
also called as Cowper’s gland, located below the prostate gland.
these glands produce alkaline fluid to counteract the acidic environment in
the urethra and serves as a lubricant during sexual intercourse.
This secretion is the first to pass down the urethra when a man becomes
sexually active.

24. MALE REPRODUCTIVE SYSTEM
Ejaculatory Duct
 passes through the prostate gland to merge the seminal vesicles and the urethra.
Urethra
 Extends from the base of the urinary bladder to the tip of the penis.
 It has 3 main regions:
1. Prostatic urethra – surrounded by the prostate gland
2. Membranous urethra – spanning the distance from the prostatic urethra to
the penis
3. Spongy (penile) urethra – running within the length of the penis

27. MALE REPRODUCTIVE SYSTEM
Semen
 is a milky white, sticky mixture of sperm and accessory gland secretions.
 The liquid provides a transport medium and nutrients and contains chemicals that protects
the sperm and aid their movement.
 pH 7.2-7.6 (alkaline) helps neutralize the acidic environment of the vagina, thereby
protecting the sperm and enhancing their motility.
 Per ejaculation, the semen propelled is about 2-5ml but the sperm content is between 50-
130million per milliliter.
 Semen is a product of 60% from the prostate gland, 30% from the seminal vesicles, 5%
from the epididymis, and 5% from the bulbourethral glands.

28. MALE REPRODUCTIVE SYSTEM
Sperm

29. MALE REPRODUCTIVE SYSTEM
Sperm
 Head - consists of a large nucleus which contains the genetic information and 23
chromosomes. It also secretes a hyaluronidase enzyme that destroys the hyaluronic acid
of the egg cell to enter into it.
 Neck - contains centrioles (proximal centriole and distal centriole).
 Middle-piece - is a highly important part of a sperm cells because it gives energy to the
sperm, thereby allowing it to swim once inside the female reproductive system.
 Tail - is the end part of the sperm, which helps the sperm to swim in the female genital
tract

30. MALE REPRODUCTIVE SYSTEM
Male Reproductive Functions
Spermatogenesis
 refers to sperm production, begins during puberty and continues throughout life.
Testosterone Production
 During puberty, the interstitial cells are activated by luteinizing hormone (LH)
causing the production of testosterone.
 The rising blood level of testosterone in the young male stimulates his
reproductive organs to develop to adult size, underlies sex drive and causes
secondary male sex characteristics.

31. Spermatogenesis

33. Spermatogenesis

34. Spermatogenesis

35. Secondary sex characteristics in male

36. MALE REPRODUCTIVE SYSTEM