What process do corals use to obtain energy from sunlight?

Corals obtain energy from sunlight through the process of photosynthesis, which is primarily facilitated by the symbiotic relationship they have with zooxanthellae, a type of algae. These algae live within the coral's tissues and perform photosynthesis, converting sunlight into chemical energy in the form of glucose while releasing oxygen as a byproduct. This energy produced by the zooxanthellae serves as a crucial nourishment source for the coral.

The process of photosynthesis is vital for coral health because it helps sustain the energy needed for growth, reproduction, and maintenance of the coral's calcium carbonate skeleton. By relying on photosynthesis, corals can thrive in shallow, sunlit waters where they can effectively harness solar energy, thereby playing a significant role in the health and resilience of coral reef ecosystems.

The other options reflect different processes not directly linked to how corals derive energy from sunlight. For instance, respiration is a process by which organisms convert energy stored in food into usable energy, but it does not involve sunlight. Fermentation is an anaerobic process and occurs when oxygen is not available, which is not applicable to corals in the context of energy extraction from sunlight. Photosynthetic respiration combines elements of respiration and photosynthesis but is not the standard