Human Reproductive System: Anatomy & Physiology

Human Reproductive System

Male Reproductive Anatomy

In the absence of staff, an erection is achieved by blood entering the corpora cavernosa of the penile tissue above the urethra. This is surrounded by the spongy body, which widens to form the glans, covered by the foreskin.

The corpora cavernosa are spongy, erectile tissue (tissue capable of becoming erect when filled with blood). This tissue has abundant cavernous spaces formed by a network of trabeculae, composed of collagen, elastic, and muscle fibers. At the base of the penis are the Cowper glands, which secrete lubricating fluid to facilitate intercourse.

Female Reproductive Anatomy

Gonads: Ovaries

Almond-sized, housed in the abdominal cavity. Within the cortex (outer layer) of each ovary are follicles containing eggs. These follicles are larger closer to the surface. The outermost are called Graafian follicles and contain eggs ready for release. The ovaries also produce female sex hormones.

Reproductive Routes: Oviducts, fallopian tubes, or uterine tubes

These tubes have a funnel-shaped opening, the infundibulum (which collects eggs). Ciliated cells in the oviducts help move the eggs. They also secrete fluid to aid movement and nourish the zygote (if fertilized) before it reaches the uterus. In some animals, there are oviparous glands that coat the eggs with various substances, forming the shell.

Uterus or womb: An empty cavity where the fallopian tubes empty. Implantation of the zygote and development of the new individual occur here. The muscle layer, the myometrium, is covered by the uterine lining, or endometrium. The bottom, or cervix, connects to the...

Vagina: An elastic canal with lubricating glands. Receives the penis during intercourse.

External Genital Organ: Vulva

Skin folds (labia) cover the clitoris (with erectile tissue similar to the penis). On the labia are Bartholin's glands of external secretion (producing lubricating fluids to facilitate mating). In some invertebrates and some species of salamanders, birds, and bats, there are seminal receptacles (sacs) where the female stores sperm, which are released when conditions are right for fertilization (depending on food availability, environmental conditions, etc.).