Biology · Human Reproduction · NEET
From the ovary to the uterus, the order is: infundibulum, then ampulla, then isthmus. The infundibulum is the funnel-shaped part closest to the ovary. Its edges have finger-like fimbriae. The infundibulum leads into the wider ampulla, and the last part, the isthmus, has a narrow lumen and joins the uterus. NCERT lists exactly this order, so learn it as a one-way path: ovary to infundibulum to ampulla to isthmus to uterus.
Fertilisation happens at the ampullary-isthmic junction, which is the point where the wider ampulla meets the narrow isthmus. It does NOT happen in the uterus, cervix or vagina. NEET 2016 tested this: both the ovum and the sperms must reach the ampullary-isthmic junction of the fallopian tube at the same time for fertilisation to occur. So remember: the ampulla region is the fertilisation site.
The ampulla is the wider part of the oviduct in the middle, and it is the site of fertilisation. The isthmus is the last part, it has a narrow lumen, and it joins the uterus. Easy way to remember: Ampulla = Ample (wide) space where sperm meets egg; Isthmus = narrow neck that connects to the uterus. Their junction (ampullary-isthmic junction) is where the ovum and sperm meet.
Fimbriae are finger-like projections on the edges of the infundibulum. Their job is to collect (pick up) the ovum after ovulation and guide it into the oviduct. Do not confuse fimbriae with the whole infundibulum: the infundibulum is the funnel, and fimbriae are the fringes on the mouth of that funnel. Without fimbriae, the released ovum could miss the tube.
The infundibulum is part of the FEMALE reproductive system, it is the proximal funnel-shaped part of the oviduct. This is a classic NEET trap. ReNEET 2026 asked which structure is NOT part of the male reproductive system and the answer was infundibulum, because rete testis, vasa efferentia and epididymis are all male ducts, but the infundibulum belongs to the oviduct.
Each fallopian tube (oviduct) is about 10-12 cm long. There is a pair of them, one on each side. Each tube extends from the periphery of each ovary to the uterus. Remember the number 10-12 cm for direct fact-based NEET questions.
Fertilization in humans is practically feasible only if:
Which of the following structures is not a part of the male reproductive system?
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Yes. Oviduct and fallopian tube mean the same structure in humans. NCERT uses both terms for the 10-12 cm tube that carries the ovum from the ovary toward the uterus.
The ampulla is the wider part of the oviduct. It is the middle region and the site of fertilisation. The isthmus, in contrast, has a narrow lumen.
The isthmus is the last part of the oviduct and it joins the uterus. So the path ends: isthmus opens into the uterus (also called the womb).
Fimbriae are the finger-like edges of the infundibulum, not the ampulla. They collect the ovum after ovulation and pass it into the oviduct.
It is the exact site of fertilisation and a repeated NEET answer. Knowing it lets you reject trap options that place fertilisation in the cervix, uterus or vagina.
