Final answer:
The fimbriae of the fallopian tubes serve to sweep the egg released during ovulation into the tube, aiding in its journey toward the uterus. The cilia and smooth muscle contractions in the oviducts assist in moving the egg or embryo towards the site of fertilization and ultimately to the uterus for development.
Step-by-step explanation:
The Function of Fimbriae in the Fallopian Tubes
The reason for the fimbriae of the fallopian tubes is closely related to the process of fertilization. The fallopian tubes, also known as oviducts, have lateral ends that flare out into a trumpet-like structure with finger-like projections called fimbriae. During ovulation, when an egg is released, these fimbriae facilitate the movement of the non-motile egg into the fallopian tube, starting its journey toward the uterus. The cilia lining the walls of the oviducts beat in the direction of the uterus, while the surrounding smooth muscle contracts to move the egg or embryo along. Fertilization typically occurs within the fallopian tubes, and it usually takes about a week for the egg or embryo to travel through the oviduct and reach the uterus for development.
The fimbriae and the coordinated movements of the cilia and smooth muscle are crucial as they contribute to guiding the egg from the ovary into the fallopian tube, and subsequently towards the uterus, promoting the chance of successful fertilization and subsequent implantation of the embryo.