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Private parts

See facts about male and female genitals and breasts

  • The shaft of the penis contains three cylinders of sponge-like tissue. During arousal these fill with blood, producing an erection.

  • The ‘glans’ (head) is loaded with nerve endings, making it extremely sensitive to touch, particularly during arousal.

  • The ‘corona’ is the flared part of the glans where it meets the shaft and in many men is the most sexually sensitive part of the penis.

  • The testicles are part of the body’s endocrine (hormone) system and produce the primary male sex hormone, testosterone.

  • During puberty, the testicles produce a large amount of testosterone, which stimulates sperm production and causes the voice to deepen, muscles to develop and hair to grow on the face and body.

  • The optimum temperature for sperm production is three to five degrees cooler than body temperature. This is why the testicles hang outside of the body.

  • On average, the testicles produce approximately 150 million sperm each day.

  • A ‘normal’ ejaculate contains at least 40million sperm.

  • It only takes one sperm to get a woman pregnant.

  • The average size of an erect penis is between 5 and 7 inches.

  • When becoming erect, a large flaccid penis does not increase proportionately in size as much as a smaller flaccid penis.

  • The size of a penis bares no relation whatsoever to a man’s fertility.

Photos courtesy of Snap Your Chap

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