Question

Ostium is the aperture present in
Α. Cloaca
B. Fallopian tube
C. Ovisac
D. None of the above

Answer 1

Hint: In female reproductive parts, the proximal tubal opening that is, present in the uterus at the utero-tubal junction and can be accessed by hysteroscopy. And the level of other distal tubal opening opens in the infundibulum of the uterine tube in the abdominal cavity.

Complete Answer:
- Female reproductive system is mainly composed of a pair of ovaries, fallopian tubes, uterus, vagina. Assessor glands and external genital organs. These all organs have different and performs some important function for the production of female gametes, fertilization, provide proper environment for the foetus, regulation of female sex hormones, etc.
- A funnel-shaped structure, called an infundibulum is present in the closer part of the ovaries. This infundibulum possesses some finger-like projections which are known as fimbriae. Fimbriae are associated in the collection of the female gametes after the ovulation.
- The infundibulum leads to a wide part of the fallopian tube which is ampulla. The last part of the fallopian tube is isthmus which has a lumen which oviduct or fallopian tube may be proximal or distal.

Now let us find solution from the given options:
- Cloaca: it is a common chamber in which intestinal, genital and urinary chambers open. It is commonly found in birds and ostia is not present in them.
- Fallopian tube: In female reproductive parts, the proximal tubal opening that is ostia, present in the uterus at the utero-tubal junction and can be accessed by hysteroscopy.
- Ovisac: it is the inner layer of the graafian follicle that consists of an ovum or ova and is usually found in vertebrates but it does not possess ostia.

Hence the correct answer is option B.

Note: Accessory ducts of the female reproductive system are usually made up of a pair of oviducts, uterus and vagina. Fallopian tube of the female reproductive system is about 10-12 cm in length and these tubes help in the association of the periphery of the ovary to the uterus.