System

testes

ducts

accessory glands

• seminal vesicles

• prostate gland

• bulbourethral gland

penis

conveyance system for urine and semen

Testes

exocrine gland/organ

thick connective tissue layer

• tunica albuginea

tunica vascularis

tunica vaginalis

• remnant of descent of testes

subdivided into lobules

• approximately 250 pyramidally shaped compartments called lobuli testis

• each with 1 to 4 seminiferous tubules

  • about 70 centimeters long each and 150 to 250 micrometers diameter

  • exocrine portion

  • produce sperm

  • cells types

    • Sertoli cells

      • triangle shaped

      • supportive

        • wraps around to nourish developing sperm

    • spermatogenic cells

      • produce sperm

      • subtypes

        • spermatogonia

          • 2n

          • germ cells

          • closest to base

          • type a

            • continues as stem cells

          • type b

            • will become spermatid

            • as formed are pushed to center

        • spermatocytes

          • I are less mature

          • II are more mature

        • spermatid

          • spermatogenesis

            • the process of the cell developing through spermatocytes to spermatids

            • grow tail (flagellum)

            • removal of excess cytoplasm and organelles

        • spermatozoa

          • mature sperm

          • nucleus is haploid

          • acrosome in the head for fertilization

            • enzymes to burrow into egg

          • midpiece has lots of mitochondria and the microtubule core of flagellum

    • Cells of Leydig

      • source of testosterone

      • found in spaces between seminiferous tubules

        • spaces are called interstitial spaces

          • so could be called interstitial cells

        • also have macrophages and fibroblasts

Movement of sperm

seminiferous tubules

straight tubules

rete testis

canaliculi efferents

caput epididymis

Epididymis

highly coiled tube

4-7 cm

function

• storage

• capacitation

  • maturation of sperm into ability to fertilize

lumen full of spermatids

mucosa

• pseudostratified columnar epithelium with lots of stereocilia

• helps to provide nourishment

  • for capacitation

• relatively smooth with stereocilia

interstium

• smooth muscle

• for movement of sperm to next portion of duct system

Vas (Ductus) Deferens

structure similar to epididymis but without stereocilia

pseudostratified columnar epithelium

smooth muscle

• inner longitudinal

• middle circular

• outer longitudinal

ampulla

• swollen end portion

• where other contents are added

  • from seminal vesicles and prostate

Seminal Vesicles

highly folded

pseudostratified columnar epithelium

secretion

• high fructose

• molecular energy for sperm to convert to mechanical energy

Prostatic Urethra

where prostate adds its secretions

largest gland in male reproductive system

• size of small walnut

30-50 tubuloalveolar glands

• simple cuboidal to columnar epithelium

• contribute milky fluid

  • rich in zinc ion, citric acid, phosphatase, and proteolytic enzymes

  • pH 6.5-7.3

  • can crystalize with age, creating deposits in the lumen called corpora amylacea

Bulbourethral (Cowper’s) Gland

more mucus gland

nuclei near bottom of cell

secretion

• amino sugars

• sialoproteins

• for lubrication of pineal urethra to add in movement of semen

Semen

average amount is about 3 mL

100M sperm per mL

• about 20% is abnormal

• about 25% is immotile

includes the secretions from the 3 glands

Urethra

urothelium mucosa

erectile tissues

• corpora cavernosa (2)

  • found further from urethra

• corpus spongiosum

  • found surrounding urethra