Male Reproductive System Flashcards
What are the organs of the male reproductive system?
Testes
System of Ducts (epidydimitis, ductus deferens, ejaculatory ducts, bulbourethral glands)
Supporting structures (scrotum, penis)
What are the testes?
Paired oval glands that produce sperm and secrete hormones.
Develop in the abdominal activity and descend into the scrotum in the seventh month of the fetal development.
Lobules
Covered by a dense white capsule that divides each teste into lobules
Each of the 200-300 lobules contains 1-3 tightly coiled seminiferous tubules
Tubules are lined with sperm forming cells called spermatogenic cells
After a sperm cell is formed it is released into the lumen of the seminiferous tubule.
What are Sertoli cells?
Nourish sperm cells and release the hormone inhibin.
What are the leydig cells?
Secrete testosterone
What is the most important androgen?
Testosterone
Promotes libido and male characteristic development
What is the scrotum?
Pouch that supports the testes.
Septum divides the strum into two sacs each containing a single teste.
Production and survival of sperm is optimal 2-3 degrees Celsius below body temp.
Maintained with scrotum outside pelvic cavity.
Cremasteric muscle raises and lowers the teste to adjust temperature.
Where does sperm production occur?
In the testes and consists of meiosis 1, meiosis 2, and spermatogenesis.
Results in the formation of four haploid sperm cells from a primary spermatocyte.
Begins during puberty and continues throughout life.
From onset until release is 65-75 days.
Spermatogonia contain the diploid number of chromosomes 2N=46
Spermatogonia undergo mitosis
One stays in tubule as stem cell spermatagonia
Other turns into primary spermatocyte
Which spermatocyte undergoes meiosis 1?
Primary, resulting in two haploid secondary spermatocyte
Which spermatocyte undergoes meiosis 2?
Secondary, resulting in four haploid secondary spermatids
What is the final stage of spermatogenisis?
One spermatocyte creating four sperm.
At what rate is sperm produced?
300 million a day
Most don’t survive 48 hrs once ejaculated
What are the major parts of sperm?
Head- DNA and Acrosome
Tail-mitochondria and flagellum
What is the epidydimis?
Tightly coiled ductus epidydimis. Stores sperm and helps propel them during sexual arousal to the vas deferens.
This is where spermat mature and acquire motility and ability to fertilize an egg
Can remain in storage for several months
What makes up the spermatic cord?
Ascending with the vas are blood vessels, nerves, lymphatic vessels and cremasteric muscle.
What are the ejaculatory ducts?
Formed by the Union of the duct of the ductus deferens and the seminal vesicles. Carry sperm to the urethra.