The Florida reef tract has experienced six mass coral bleaching events. Which of the following BEST explains mass coral bleaching events?
A. the loss of photophores, organs that give off light
B. the loss of photophores, which give coral their bright colors
C. the loss of zooxanthellae, organs that give off light
D. the loss of zooxanthellae, which give coral their bright colors
D. the loss of zooxanthellae, which give coral their bright colors
Zooxanthellae are symbiotic algae that live within the tissues of coral, providing them with energy through photosynthesis and giving coral their vibrant colors. When coral are stressed due to factors such as high water temperatures, they expel the zooxanthellae, which results in them losing their color and becoming bleached.