Penis
A cross section of the penis shows its three cylinders of erectile tissue and the urethra. The paired corpora cavernosa lie dorsally; the corpus spongiosum, lying ventrally, houses the urethra. Thin skin encloses the penis. 10x
Corpora cavernosa >
The corpora cavernosa are paired cylinders of erectile tissue, composed of venous channels (cavernous spaces) and intervening trabeculae of connective tissue and smooth muscle. The corpora are surrounded by a dense connective tissue layer called the tunica albuginea, that forms an incomplete central partition between the two cylinders.
- Tunica albuginea
The corpora cavernosa are paired cylinders of erectile tissue, composed of venous channels (cavernous spaces) and intervening trabeculae of connective tissue and smooth muscle. The corpora are surrounded by a dense connective tissue layer called the tunica albuginea, that forms an incomplete central partition between the two cylinders.
- Deep artery >
A deep artery supplies each corpus cavernosum. Branches of the deep artery supply either the trabeculae of the corpus, via nutritive arteries during the flaccid state, or the venous channels (cavernous spaces), via helicine arteries during erection.
Corpus spongiosum >
The corpus spongiosum is another cylinder of erectile tissue that lies in the ventral midline. Its tunica albuginea is less dense than that surrounding the dorsal corpora, thus ensuring that the urethra it contains will not be occluded during ejaculation. The glands of Littre are mucus-secreting glands that secrete into the urethra.
- Tunica albuginea
The corpus spongiosum is another cylinder of erectile tissue that lies in the ventral midline. Its tunica albuginea is less dense than that surrounding the dorsal corpora, thus ensuring that the urethra it contains will not be occluded during ejaculation. The glands of Littre are mucus-secreting glands that secrete into the urethra.
- Urethra
The corpus spongiosum is another cylinder of erectile tissue that lies in the ventral midline. Its tunica albuginea is less dense than that surrounding the dorsal corpora, thus ensuring that the urethra it contains will not be occluded during ejaculation. The glands of Littre are mucus-secreting glands that secrete into the urethra.
- Glands of Littre
The corpus spongiosum is another cylinder of erectile tissue that lies in the ventral midline. Its tunica albuginea is less dense than that surrounding the dorsal corpora, thus ensuring that the urethra it contains will not be occluded during ejaculation. The glands of Littre are mucus-secreting glands that secrete into the urethra.
Thin skin
The penis is covered by a layer of thin skin. The underlying subcutaneous tissue is thickened, lacks adipose tissue and has few sweat glands.
Image source >
The image was taken of a slide in the University of Mississippi slide collection.
