GENERAL HISTOLOGY

Detailed explanation-1: -The madreporite /ˌmædrɪˈpɔːraɪt/ is a light colored calcareous opening used to filter water into the water vascular system of echinoderms .

Detailed explanation-2: -The water vascular system of the sea stars open up at the madreporite, a perforated opening in the central part of the animal. Internally, the madreporite leads to a stone canal, made up of skeletal deposits. The stone canal is attached to a ring canal which leads to each of the five (or more) radial canals.

Detailed explanation-3: -The madreporite is a light-colored, calcerous opening used to filter water into the water vascular system of echinoderms. Acting as a pressure-equalizing valve, it is visible as a small red or yellow button-like structure (similar to a small wart) on the aboral surface of the central disk of a sea star.

Detailed explanation-4: -The madreporite is an essential part of the circulation system in echinoderms. Through this plate, which is also called a sieve plate, the echinoderm draws in seawater and expels water to fuel its vascular system. The madreporite functions like a trap door through which water can move in and out in a controlled manner.

Detailed explanation-5: -So, the correct answer is ‘Madreporite’.