Question

Narrow oviducts run toward the posterior end, and have expanded region called _____ _____. This gland secrets the shell as the eggs pass through this region of the oviduct.

Answer 1

The expanded region of the narrow oviducts is called the ampulla. It is where fertilization of the egg usually occurs.

Step-by-step explanation:

The expanded region of the narrow oviducts in the reproductive system is called the ampulla.

The ampulla is the middle part of the oviducts where fertilization of the egg usually occurs. It is wider than the narrow isthmus and has a ciliated epithelium that helps move the egg towards the uterus.

Additionally, the ampulla is part of the oviducts' three-layer structure, which includes an outer serosa, a middle smooth muscle layer, and an inner mucosal layer with ciliated cells.