Female Accessory Sex Organs
The female accessories include oviducts or fallopian tubules as they are generally termed in the human subjects, the uterus, the vagina and the external genitalia. In mammals, oviducts provide a passageway between the ovary and uterus. The ovarian end of this tube is expanded into a funnel, having fimbriated margin. Some of the epithelial cells lining the tube possess cilia that beat inwardly. Beating of cilia together with the increased activity of the fimbria at the time of ovulation assist the movement of the ovum towards the uterus. Fertilisation typically occurs in the oviducts. In human beings fertilisation occurs usually within 24 hours after the egg has been released from the ovary. The primate uterus is a pear-shaped muscular organ.
The uterine wall is composed of a thick mass of smooth muscle cells called myometrium and glandular lining known as endometrium. The narrow caudal end of the uterus is called cervix. During pregnancy the uterine wall becomes highly modified to facilitate implantation of the blastocyst and its subsequent development. The human vagina is an unpaired, dilated tube approximately 4 inches in length extending from the caudal end of the uterus to the vestibule. The lining of the vagina is a stratified squamous epithelium devoid of glands. It has a very thin layer of muscles. The vagina does not provide a satisfactory environment for the survival of spermatozoa. In humans, they die within a few hours, whereas they may remain viable for two or three days in the uterus and fallopian tubes.