Question

Which part of the oviduct has a narrow lumen?

Answer 1

Isthmus:

1. The small section of the oviduct that exits the uterine wall and extends laterally to the ampulla is known as the isthmus.
2. The ampulla is the enlarged section of the tube that joins the isthmus to the oviduct's infundibulum.
3. As a result, the lumen of the Isthmus is narrow.