Plankton crossword puzzle

4. Free-swimming aquatic organisms, such as fish and squid, capable of active movement.
7. Zooplankton that remain in the planktonic phase throughout their entire life cycle.
11. Organisms that produce their own food through processes like photosynthesis.
12. Microscopic organisms that drift or float in aquatic environments.
13. A bloom of harmful, often toxic, phytoplankton that can lead to the discoloration of water.
15. Planktonic organisms that spend only a part of their life cycle as plankton
16. The position an organism occupies in a food chain, indicating its feeding relationship to other organisms.
17. Pertaining to the bottom of a body of water; organisms living on or in the substrate.
19. Larger-sized plankton, visible under a microscope.

1. Small animals that feed on phytoplankton or other zooplankton
2. A close and long-term interaction between different biological species.
3. Extremely small-sized plankton, smaller than microplankton.
5. Microscopic, photosynthetic organisms that form the base of the aquatic food chain.
6. Organisms that obtain their energy by consuming other organisms.
8. Planktonic organisms that spend their entire life cycle in the planktonic phase.
9. A type of phytoplankton with a silica-based cell wall, often shaped like a glass shell.
10. Small crustaceans that are a common type of zooplankton.
14. Unicellular algae that can be both phytoplankton and sometimes bioluminescent.
17. A rapid increase in the population of planktonic organisms, often causing discoloration of the water.
18. the depth in the water column where the rate of photosynthesis equals the rate of respiration.