Human Male Reproductive System

Reproduction

• Reproduction is the process of generating new life, either sexually or asexually, resulting in an offspring and propagating the species.
• Humans reproduce sexually through the use of both male and female reproductive systems.

Male Reproductive System

• The male reproductive system is composed of both external and internal organs that assist in the process of sexual reproduction.
• The main organs of the male reproductive system are:
  • Penis
  • Scrotum
  • Testes (Testicles)
  • Epididymis
  • Vas Deferens
  • Ejaculatory Ducts
  • Urethra
  • Seminal Vesicles
  • Prostate Gland
  • Bulbourethral Glands

External Male Reproductive Structures

• External organs of the male reproductive system are present outside the body and are mainly utilized in the act of sexual intercourse.
• The three main organs are:
  • Penis
  • Scrotum
  • Testes

Penis

• The penis is the organ directly involved in sexual intercourse.
• It is composed of three parts: the root, body, and glans.
• The glans is sometimes covered with a layer of skin called the foreskin.

Scrotum

• The scrotum is a loose sac-like structure that encapsulates the testes and provides the climate necessary for testes' function.
• Its walls contain muscles that contract in response to temperature changes.

Testes

• Testes are oval-shaped organs that are the site of sperm production.
• Within the testes, structures called the seminiferous tubules produce the male gametes.
• The testes produce testosterone, which are the primary male hormones.

Internal Male Reproductive Organs

• Internal male reproductive organs are present inside the body and are sometimes referred to as accessory organs.
• The internal organs include:
  • Epididymis
  • Vas Deferens
  • Ejaculatory Ducts
  • Urethra
  • Seminal Vesicles
  • Prostate Gland
  • Bulbourethral Glands

Epididymis

• The epididymis is a coiled tube present on each testicle that hosts sperm after they are produced.
• Sperm stored in the epididymis undergo further maturation, acquire motility, and reside there until ejaculation.

Vas Deferens

• The vas deferens, also called ductus deferens, are long muscular tubes that transport sperm from the epididymis to the urethra.
• An extended structure of the vas deferens named the ampulla also acts as storage chambers for semen.

Sperm Functions

• Sperm are haploid germ cells that serve as the male gamete that swims up the female reproductive tract to reach the Fallopian tubes, where the ovum is placed upon ovulation.
• Upon fertilization, sperm provides its set of haploid chromosomes (23 in humans) to complete the normal diploid chromosome set and kickstart zygote formation.

Male Reproductive System Function

• Production of sperm: sperm is produced within the seminiferous tubules of the testes in the process of spermatogenesis.
• Production of testosterone: in addition to spermatogenesis, cellular structures in the testes called Leydig cells produce testosterone.
• Sexual reproduction: the male reproductive system is responsible for the placement of sperm into the female reproductive system in order for fertilization and zygote formation to occur.

Learn about the male reproductive system and its role in sexual reproduction, including the production of gametes and the formation of a zygote.