The Human Body


Ovary, in anatomy, is the organ of female animals, including humans, that produces reproductive cells called eggs, or ova (see Reproductive System). In humans they are oblong, flattened, ductless glands, about 3.8 cm (about 1.5 in) long, on either side of the uterus, to which they are connected by the fallopian tubes. Each ovary is composed of two portions: an external, or cortical, portion, and a deep, medullary portion. The cortical portion in the adult contains an enormous number of follicles, or sacs, varying in size. Called Graafian follicles, they contain the ova, the female reproductive cells. The ovary secretes hormones that, together with secretions from the pituitary gland, contribute to secondary female sexual characteristics and also regulate menstruation. The union of the male sperm cell with the ovum results in fertilization.

For a discussion of ovaries in plants, see Flower; Fruit; Ovule.