Coral reefs involve a __________________________ relationship between the coral polyps and zooxanthellae that live in the tissues of the polyps.

Coral Polyps

Small, soft-bodied organisms that are the primary builders of coral reefs, living in large colonies where they secrete calcium carbonate to form the reef's structure.

Zooxanthellae

Microscopic algae that live symbiotically within the cells of coral and other marine organisms, providing them with nutrients through photosynthesis.