In Depth: Reproductive Organs
Humans are sexual, meaning a male and a female are needed to reproduce. Each is equipped with specific organs capable of producing specific cells to procreate.
Together with a woman’s reproductive organs, sexual intercourse can lead to the reproduction of human life.
For men, the external reproductive organs include:
- Penis: This tubular muscular organ becomes filled with blood during arousal, thus making sexual intercourse possible.
- Scrotum: This pouch-like sac hangs below the penis and encases the testes, or testicles.
- Testicles: These two oval shaped organs produce sperm cells and testosterone.
While all men are born with all of their sexual organs, they don’t begin to function fully until puberty. The common age of puberty is around 12. During this time, hormone changes affect a boy’s gonads and create lasting changes that have typically been viewed through history as when a boy “becomes a man.” This process affects many changes, such as growth, muscular build, hair growth on the genitals, face, and other parts of the body.
In terms of reproduction, puberty signals the time when a man has fully-functioning sexual organs and is capable of procreation.
The male testes produce spermatozoa (more commonly referred to as sperm), which is released at sexual climax. This is known as ejaculation. The sperm leaves the penis in a mixture of secretions designed to nourish and transport the cells into the female reproductive system for procreation.
There are up to 750 million sperm cells in each ejaculation, but it only takes a single sperm cell to fertilize a woman’s egg.
The testes also produce the hormone testosterone that is directly absorbed into the bloodstream. Along with producing sperm and maintaining sexual function, testosterone also creates common features that physically distinguish men from women, such as facial hair, deeper voice, more muscle mass, and broader shoulders.
As a man ages, sexual function typically diminishes. Typical sexual dysfunction in men include:
- Impotence (erectile dysfunction)
- Low sperm count
- Lowered testosterone
- Testicular cancer
- Prostate cancer