Final answer:
The incorrect association of structure and function is 'Stone canal - Respiration' as the stone canal is part of the water vascular system used for locomotion and feeding, not for respiration.
Step-by-step explanation:
The incorrect association of structure and function in sea star anatomy is:
Stone canal - Respiration.
In echinoderms like sea stars, the madreporite is a structure that regulates the amount of water entering the water vascular system, which is not primarily for water filtration but for regulating hydrostatic pressure to aid in locomotion and feeding. The tube feet serve as a means of locomotion, utilizing the water vascular system to move.
The pyloric stomach is indeed associated with digestion, breaking down food that the sea star consumes. However, the stone canal, which is part of the water vascular system and connects the madreporite to the ring canal, is not linked to respiration; therefore, it is the incorrect association. Seas stars primarily respire through their body surface and other specialized structures called papulae or dermal branchiae.