Describe the structure and function of the Penis, and state the primary functions of the Testis, Scrotum, Sperm duct, and Urethra based on a diagram.

Okay, here's a question and answer based on the provided text and diagram.

Question: Based on the provided text and diagram of the male reproductive system, describe the structure and function of the Penis, and state the primary functions of the Testis, Scrotum, Sperm duct, and Urethra.

Answer:
Here are the descriptions and functions of the specified parts of the male reproductive system:

• Penis: It is the organ used for penetrating the vagina during sexual intercourse. Its structure consists of muscles, mainly blood vessels, and spongy tissues containing numerous spaces. These spaces fill with blood to make the penis erect for sexual intercourse.
• Testis: The primary function is to produce sperm (male sex cells) and male sex hormones, such as testosterone.
• Scrotum: This is a sac of skin that holds and protects the testes, maintaining them at a slightly lower temperature than the body, which is essential for sperm production.
• Sperm duct (Vas deferens): Its function is to transport mature sperm from the epididymis (located near the testis) to the urethra.
• Urethra: This tube serves a dual function in males: it carries urine from the bladder out of the body, and it also carries semen (sperm mixed with fluids) out of the body during ejaculation.