Male reproductive system (LAB)

Seminal gland

ejaculatory duct

the vas deferens enlarges to form the region called the ampulla, which empties into the ejaculatory duct.

-union of ductus deferens and duct of seminal vesicles

-Empties sperm and seminal fluid into prostatic urethra

prostate

-Produces up to 20% of the semen & includes nutrients & enzymes to activate sperm, alkaline, opaque whitish

-Encircles the upper part of the urethra

bilbo-urethral gland

Pea-sized gland inferior to the prostate

Produces a thick, clear mucus

Cleanses the urethra of acidic urine

Serves as a lubricant during sexual intercourse

Secreted into the penile urethra

Ductus vas deferens

Elongated comma shaped structure runs along the posterolateral aspect of the testis, and caps its superior aspect. It is the site for sperm maturation.

epididymis

-Functions to mature and store sperm cells (at least 20 days)

-Expels sperm with the contraction of muscles in the epididymis walls to the vas deferens

testis

scrotum

Glans penis

Testis

male gonads, produce sperm and hormones

- are the primary reproductive organ of the male, producing both sperm and testosterone.

1-Secrete male sex hormones (androgens) such as Testosterone 2-Produce male gametes (spermatozoa or sperm)

seminiferous tubules

Testes are divided into lobules with seminiferous tubules inside, where sperm are produced

-each lobules contains 3 -4 highly collied

interstitial endocrine cells (leydig) cells

are found in the connective tissue surrounding the seminiferous tubules and produce testosterone

septa testis

tunica albuginea

rete testis

-sperm is emptied here

transports sperm to epididymis

sertoli cells

spermatogonia

divide to produce Type A daughter cell that maintain the stem cell line and type B daughter cells that get pushed toward the lumen to become primary spermatocytes and ultimately sperm.

primary spermatocytes

undergoes Meiosis I and meiosis II to form spermatids (n).

Spermatids

-are haploid (n)are not functional gametes yet, they are not motile cells.

-are pushed into the lumen of the seminiferous tubule and are stripped from their excess cytoplasm and form a tail, resulting in a sperm with a head, mid-piece and a tail.

As spermatogenic cells and primary spermatocyte cells mature, they are moved towards the center of the seminiferous tubule. The spiral "hairs" in the center are the flagella of developing spermatids and sperm.

Periphery of the tubule

The cells in this area are the spermatogonia. About half of these will form primary spermatocytes, which begin meiosis. These are recognizable by their pale-staining nuclei with centrally nucleoli.

-The remaining daughter cells resulting from mitotic divisions of spermatogonia stay at the tubule periphery to maintain the germ cell line.

Observe the cells in the middle of the tubule wall.

There you should see a large number of spermatocytes that are obviously undergoing a nuclear division process. You will find clumps of chromatin. The primary spermatocytes are larger than the secondary spermatocytes that will undergo division and spermiogenesis.

THE LUMEN OF THE TUBULE:

Identify the small round-nucleated spermatids,

many of which started to lose the or cytoplasm.

Sustenocyte

Sertoli cells: from the periphery

of the tubule; They nourish the spermatids during

sperm transformation.

Anatomy of Sperm

Head

-Helmet like acrosome covers nucleus that contains DNA.

-stores Hydrolytic enzymes needed to penetrate egg

•Middle Piece

-contains mitochondria that provide energy for movement.

•Tail (= Flagellum)

- for movement

Ductus deferens

It is enclosed along with blood vessels and nerves in the spermatic cord.

-Carries sperm from the epididymis to the ejaculatory duct

-Passes through the inguinal canal and enters the pelvic cavity over the urinary bladder.

-Moves sperm by peristalsis

-Ends in the ejaculatory duct which unites with the urethra

Urethra

Shared by reproductive and urinary systems, Both semen and urine pass through it. Has three parts.

Extends from the base of the urinary bladder to the tip of the penis

Carries both urine and sperm

Sperm enters from the ejaculatory duct

Ends at the External urethral orifice

Seminal Vesicles

Located at the posterior and base of the bladder

Produces a thick, yellowish secretion (60% of semen)

Fructose (sugar)

Vitamin C

Prostaglandins

Join the ductus deferens to form the ejaculatory duct

dartos muscle.

In the dermis, there is a thin layer of smooth muscle known as the dartos muscle. Contractions of this muscle causes wrinkling of the skin

cremaster muscle

thicker layer of skeletal muscle that lowers and raises the testes based on temperature.

Prepuce

corpora cavernosa

Internally there are three areas of elongated cylinders spongy erectile tissue around the urethra. They engorge with blood and become rigid during erection.

corpus spongiosum.

Semen

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