Final answer:
The unpaired male reproductive structure is the Prostate gland. It produces fluid that is a major component of semen. Other paired structures include the epididymis, seminal vesicles, bulbourethral glands, and the corpus cavernosum.
Step-by-step explanation:
The male reproductive structure that is unpaired, meaning there's only one in the body, is E) the Prostate gland. Each of the other structures listed are paired with one on each side of the male body, except for the prostate gland, which is a single, walnut-sized gland located below the bladder that surrounds the urethra. The prostate gland produces a fluid that is a major component of semen, helping to nourish and transport sperm.
Other facts about the male reproductive system include:
- Spermatogenesis, the process of sperm production, takes place in the seminiferous tubules of the testes.
- Structures such as the epididymis, vas deferens, and urethra are all involved in the transport of sperm from the testes to the outside of the body.
- The bulbourethral gland, also known as Cowper's gland, produces a pre-ejaculate fluid that is part of semen but is primarily associated with lubrication.
Regarding urinary structures, the urethra is involved both in the male reproductive system by transporting sperm and in the urinary system by carrying urine from the bladder to the outside of the body.