Male reproductive system

• • The prostate gland surrounds a portion of the urethra and secretes a slightly alkaline milky fluid as part of semen.
  • The seminal vesicles secrete a thick fluid that nourishes the sperm.
  • Cowper's glands produce thick clear mucus prior to ejaculation.
  • The bladder stores urine until it is released through the urethra.
  • The urethra carries semen and urine out of the penis.
• Parts of the Male Reproductive System:

  • The penis is made of two parts: the shaft and the glans. It deposits sperms into the vagina during mating.
  • The scrotum is a pouch-like structure that keeps the testicles at the right temperature, ideal for sperm production.
  • The two testicles produce sperm and the male sex hormone testosterone.
  • The Epididymis is where sperm is temporarily stored before being transported to the vas deferens.
  • The vas deferens is a thin muscular tube that transports sperm from the epididymis to the urethra.
• Functions of the Male Reproductive System:

  • Produces sperm cells (male gametes) and delivers them inside the female reproductive system.
• Testes: The sites of sperm production:

  • Spermatogenesis is the process of producing sperm cells in the seminiferous tubules in the testes.
  • Meiosis is the process that reduces the number of chromosomes from diploid to haploid.
  • The testes begin to produce sperm after males reach puberty, usually between the ages of 9 and 14.
• Mature Sperms in Epididymis:

  • Sperm cells, together with the secretions of the glands and reproductive ducts, make up semen.
  • Semen composition is around 95% secretions from the glands and 5% sperm.
• Male and Hormones and their functions:

  • Luteinizing hormone (LH) stimulates the secretion of testosterone.
  • Follicle-stimulating hormone, along with testosterone, stimulates sperm production in the seminiferous tubules.
  • Testosterone is produced by cells located between the seminiferous tubules and is responsible for the development of secondary male characteristics during puberty.
• The Human Sperm Cell:

  • Mature sperm cell consists of three parts: Head, Midpiece, and Tail.
  • The head contains the chromosomes and acrosome, the midpiece contains mitochondria, and the tail is a powerful flagellum that enables movement.
• How are sperm cells being delivered:

  • About 3.5 mL of semen is expelled during ejaculation, containing 300 to 400 million sperm cells.
  • If any sperm does not penetrate the egg cell, fertilization does not occur.
• Cryptorchidism:

  • Refers to undescended testicles, a condition where one or both testicles fail to move into the scrotum before birth.
• Spermatogenesis is the process by which sperm cells develop from germinal epithelium cells within seminiferous tubules.
• The testes are the male gonads, which produce sperm cells (gametes) and secrete hormones.
• Each testis contains about 250 coiled seminiferous tubules that contain sperm-producing cells called Sertoli cells.
• Meiosis is the division of diploid germinal epithelial cells into haploid sperm cells.
• During meiosis, homologous pairs of chromosomes line up at metaphase and exchange genetic material through crossing over.
• In humans, there are two types of sex chromosomes: X and Y.
• Each testis has an outer layer called the tunica albuginea, which surrounds the lobules.
• Within each lobule, there are many coiled seminiferous tubules lined with germinal epithelial cells.
• Inside the seminiferous tubule, there are two types of cells involved in spermatogenesis: Germinal epithelial cells and Sertoli cells.
• During meiosis, four daughter cells are produced with half the number of chromosomes as the parent cell.
• Interstitial Leydig cells are found between the seminiferous tubules and secrete testosterone.
• Germinal epithelial cells undergo mitosis to form primary spermatocytes, which then divide through meiosis to become secondary spermatocytes.
• Germinal epithelial cells undergo mitosis to form primary spermatocytes, which then divide through meiosis to become secondary spermatocytes.
• In humans, there are two types of sex cells: XY gamete and XX gamete.
• At anaphase, sister chromatids separate and migrate to opposite poles of the cell.
• At anaphase II, one member of each pair separates to opposite poles of the cell.
• Germinal epithelial cells undergo mitosis to form primary oocytes, which then enter prophase I of meiosis.
• Secondary spermatocytes further divide through meiosis II to create spermatids, which mature into functional spermatozoa with tails.
• Male gamete production involves the fusion of a sperm nucleus with an ovum nucleus during fertilization.
• Spermatogenesis occurs within the seminiferous tubules, where spermatozoa develop from stem cells called spermatogonia.
• Male gametogenesis produces spermatozoa or sperm cells.
• The interstitium between the lobules contains Leydig cells, which produce testosterone.
• Spermatogenesis occurs within the seminiferous tubules, where spermatozoa develop from primordial germ cells.
• Spermatocytes undergo mitosis to form primary spermatocytes, then enter meiosis to become secondary spermatocytes.
• Spermatogonia divide by mitosis to produce primary spermatocytes, which undergo meiosis to form secondary spermatocytes.
• Secondary spermatocytes divide again by meiosis II to form spermatids, which mature into spermatozoa with tails.
• Testicular descent involves the movement of the testes downward to their final position outside the abdomen.
• The process of spermatogenesis takes about 74 days.
• Secondary spermatocytes further divide to become spermatids, which mature into spermatozoa (sperm).
• The female reproductive system includes the vagina, cervix, uterus, ovaries, and fallopian tubes
• Vagina:

  • A muscular canal that joins the cervix to the outside of the body
  • Can widen to accommodate a baby during delivery and shrink back to hold something narrow like a tampon
  • Lined with mucous membranes to keep it moist