Question

Which of the following glands are responsible for about 70% of the volume of semen?

1) the pituitary
2) the prostate
3) the seminal glands
4) the bulbo-urethral glands

Answer 1

The seminal glands (seminal vesicles) are responsible for about 70% of the volume of semen, producing a thick, yellowish, alkaline solution that makes up 60% of the bulk of semen. The other glands involved in semen production are the prostate gland and the bulbourethral glands.

Step-by-step explanation:

The glands responsible for about 70% of the volume of semen are the seminal glands (also known as the seminal vesicles).

The seminal glands are a pair of glands that lie along the posterior border of the urinary bladder and produce a solution that is thick, yellowish, and alkaline. This solution makes up about 60% of the bulk of semen and contains mucus, fructose, a coagulating enzyme, ascorbic acid, and local-acting hormones called prostaglandins.

The other glands involved in semen production are the prostate gland (contributes close to 30% of semen) and the bulbourethral glands (contribute a small amount of fluid to semen).

Answer 2

The seminal vesicles are the glands responsible for about 70% of the volume of semen, producing a solution that provides nutrients and an alkaline environment for sperm within semen. The correct answer to the question is 3) the seminal glands.

Step-by-step explanation:

The gland responsible for about 70% of the volume of semen is the seminal vesicles. Semen is the thick, milky fluid that contains sperm and is ejaculated during sexual intercourse. The seminal vesicles, located near the posterior border of the urinary bladder, produce a solution that not only contributes to the bulk of semen but also provides an alkaline environment essential for sperm mobility. This fluid is rich in substances like fructose, which provides nutrients for the sperm, as well as prostaglandins and other compounds that support the survival and motility of sperm within the female reproductive tract.

The prostate gland contributes nearly 30% of the semen volume with a fluid that contains high concentrations of zinc, essential for sperm health. Meanwhile, the bulbo-urethral glands (or Cowper's glands), although they play a role in secreting a lubricating fluid, contribute much less to the semen volume. Hence, the seminal glands are responsible for most of the semen volume.

Therefore, the correct option is 3) the seminal glands.