What is normal penis anatomy?

The penis contains two chambers, called the corpora cavernosa, which run the length of the upper side of the penis . The urethra, which is the channel for urine and ejaculate, runs along the underside of the corpora cavernosa. Filling the corpora cavernosa is a spongy tissue consisting of smooth muscles, fibrous tissues, spaces, veins, and arteries. A membrane, called the tunica albuginea, surrounds the corpora cavernosa. Veins located in the tunica albuginea drain blood out of the penis