No. Zooplankton feed on phytoplankton. Phytoplankton cannot photosynthesize in the dark. (The Benthric Zone is the lowest level of the ocean/a body of water, no sunlight can really reach there.)
The tropical rainforest is the biome that tends to get the most rainfall.
The spinal cord and the brain make up the central nervous system, and spinal cord nerves carry most messages between the brain and the rest of the body.
The vagus nerve carries the signal from the brain to the heart.