Examine a section of the penis and identify the folded mucosa of the urethra. What type of epithelium is present? Near the urethra, identify the small paraurethral glands.

Identify the corpus cavernosum urethrae (or corpus spongiosum) surrounding the urethra. Next to this, dorsally, identify the paired corpora cavernosa penis. These bodies together represent three cylinders of erectile cavernous tissue. Within them identify the helicine arteries and the large vascular sinuses in the connective tissue surrounding the arteries.

Clinical note: The target of the drug Viagra, used to treat impotence or erectile dysfunction, is the population of smooth muscle cells in the microvasculature of the corpora cavernosa, increasing the contractility of these cells and facilitating the events that lead to the cavernous tissue filling with blood.

What cell type(s) in the penis are acted on by Viagra?

Now for the female reproductive system.