Final answer:
The Cowper's glands, or bulbourethral glands, secrete a clear fluid that lubricates the male urethra, neutralizes urine acidity, and prepares it for semen passage during ejaculation. This secretion is also part of the semen and may contain a few sperm, which can affect the reliability of withdrawal as a birth control method.
Step-by-step explanation:
The Cowper's glands, also known as the bulbourethral glands, are a pair of small glands in the male reproductive system. These glands are responsible for secreting a clear, alkaline fluid that plays several important roles. The secretion from the bulbourethral glands helps to lubricate the urethra and neutralize any residual acidity from urine, thus preparing the urethra for the passage of semen. This secretion occurs prior to ejaculation and may contain a small number of sperm, which is why the withdrawal method of birth control can be unreliable.
The fluid produced by the bulbourethral glands is rich in proteins and has a thick, saline consistency. It contributes to the overall volume of semen, although it makes up only a tiny percentage. The secretion released by these glands occurs shortly after sexual arousal, before the release of the bulk of the semen. The bulbourethral glands are located below the prostate gland, each with a short duct leading into the urethra. The function of these glands is also to help ensure the semen has a viable environment by cleansing the urethra from any acidic urine that could harm sperm.