Across
- 3. The measure of the biomass that is present within an area.
- 5. The area of an ocean that receives enough light to sustain photosynthesis.
- 6. Organisms that are fixed to their environment.
Down
- 1. corals that are reef-building and contain zooxanthellae.
- 2. Animals without a spine.
- 4. The variety of different life forms that define a community or ecosystem.