The male reproductive system has two main parts: the external genitalia and internal genitalia. The internal genitalia include the testes, epididymides, vas deferens, seminal vesicles, prostate gland, and urethra. The penis is made up of three parts: the root, the body, and the glans. It is also known as the male member, prick, cock, dick, dong, pecker, wiener, tool, rod, or manhood. It serves several functions including excretion, reproduction, pleasure, dominance, and protection. The human penile shaft consists of two corpora cavernosa and one corpus spongiosum. The corpora cavernosa are elastic chambers that run the length of the shaft and contain sinusoidal blood vessels and smooth muscle tissue. They become engorged during sexual arousal when blood flow increases into them, causing the penis to swell and erect. The corpus spongiosum runs along the underside of the corpora cavernosa and contains the urethral opening at its tip. It provides rigidity to the penis by filling with blood during an erection. When a person becomes sexually aroused, nerves in the brain send signals to the endothelium lining the blood vessels in the corpora cavernosa. This causes the vessels to relax and allow more blood to flow in, making the penis expand. At orgasm, the smooth muscles of the corpora cavernosa contract and force the accumulated blood out, leading to ejaculation and temporary flaccidity. Penises come in different sizes, shapes, colors, and textures. Some men have large or small penises; some are curved, straight, thick, thin, veiny, wrinkly, smooth, uncircumcised, circumcised, or foreskin-free. They can also vary in sensitivity, strength, flexibility, firmness, and longevity.
The penis is not only used for reproduction but can also bring pleasure and intimacy. During foreplay, stimulation of the glans, shaft, and scrotum leads to increased blood flow and arousal. Masturbation involves touching or rubbing the penis to induce orgasm without intercourse. It can help relieve tension, reduce stress, boost self-esteem, and improve sleep quality. Sexual relationships require trust, communication, consent, respect, honesty, empathy, patience, understanding, appreciation, gratitude, and affection. They involve physical contact, verbal expression, emotional connection, and shared pleasure. Good sexual health requires regular exercise, nutrition, hygiene, rest, protection, and medical care.
This article explores the anatomy of the penile shaft, its functions during sexual arousal, and the role it plays in sexual relationships. The penis consists of two corpora cavernosa and one corpus spongiosum, which become engorged with blood during an erection. Its size, shape, texture, and sensitivity vary from person to person. Foreplay, masturbation, and sexual relationships offer pleasure, intimacy, and wellbeing.