Which organ is NOT part of the male reproductive system?

The uterus is not part of the male reproductive system because it is a specific organ found in the female reproductive system. Its primary function is to house and nurture a developing fetus during pregnancy. In contrast, the male reproductive system includes structures designed for the production, maintenance, and transport of sperm and male hormones. The prostate gland, ductus deferens, and testis all play essential roles in the male reproductive process: the prostate contributes fluid to semen, the ductus deferens transports sperm from the testes, and the testis produces sperm and testosterone. Understanding the distinct roles and functions of these organs highlights why the uterus is correctly identified as being outside the male reproductive anatomy.