The ocean is the largest aquatic biome that can be categorized into different zones. Photic zone and aphotic zone are two oceanic zones categorized vertically based on the penetration of light. Photic zone receives sunlight which penetrates the photic zone, enabling photosynthesis. The diversity of organisms is high in the photoic zone as it is more favourable for life.
The aphotic zone is the portion of the ocean that does not receive sunlight. Sunlight does not penetrate this zone. Photosynthetic organisms cannot survive in this zone due to the lack of sunlight. The diversity of organisms is low, and a few numbers of organisms live in this zone.