Across
- 3. Creatures that produce light through chemical reactions are
- 5. Deep ___ mining is the process of obtaining minerals from the sea floor.
- 6. Falling debris of dead organisms is known as marine ___.
Down
- 1. Zone with insufficient sunlight for photosynthesis.
- 2. The pressure ____ as you dive lower into the zone.
- 4. Billion of microorganisms migrate ____ towards the surface.