1. Phytoplankton

2. Phytoplankton are the plant-like organisms of the sea that carry out photosynthesis and float in the upper areas of the world’s oceans.

3. Most of the ocean is too deep for plants to attach to the bottom like this Giant Kelp off the coast of California.

4. Therefore, most of the photosynthesis is carried out by microscopic single celled organisms or chains of single cells.

5. These organisms often have long projections to increase their surface area or oils to keep them in the photic zone.

6. Types of
Phytoplankton

7. Diatoms

8. Diatoms are dominant members of the phytoplankton that can be caught in a net.

9. They are especially common in temperate , coastal and polar regions.

10. They have sculptured shells, or frustules, made of silica
They have sculptured shells, or frustules, made of silica. Diatoms can come in a variety of shapes.

11. More Diatom Shapes

12. Life Cycle of a Diatom

13. Some diatoms, like this one can kill fish when found in large numbers
Fish Killer
Some diatoms, like this one can kill fish when found in large numbers

14. The glasslike projections cause mucus to build up in the fish’s gill which can lead to the fish's death.

15. Dinoflagellates

16. Dinoflagellates are found throughout the world’s oceans, but tend to prefer warmer areas. Given nutrients, dinoflagellates can bloom or explosively grow to huge numbers sometimes causing RED TIDES

17. Dinoflagellates:
red tides
Florida red tide organism:
Gymnodinium breve

18. Around 60 species of Dinoflagellates are known to cause red tides.
A few species produce poisons that are among the most powerful natural toxins known.

19. Red tides can also threaten human health.
During a red tide, dinoflagellates may poison the waters, turning the surface into a sea of dead fish.
Red tides can also threaten human health.

20. People who eat the shellfish can get Paralytic Shellfish Poisoning.
Mussels, clams and other bivalves store the toxins as they filter feed.
People who eat the shellfish can get Paralytic Shellfish Poisoning.

21. Victims suffer numbness and tingling, loss of balance, slurred speech, and in extreme cases, paralysis and death!

22. Symbiotic Dinoflagellates
Some dinoflagellates like Zooxanthellae, are symbiotic with corals or jellyfish.

23. Coccolithophorids

24. Coccolithophorids are common members of the nanoplankton
Coccolithophorids are common members of the nanoplankton. Most are too small to be taken in a regular plankton net.

25. Though found in coastal waters, they do best in open oceans where they often far outnumber all other types of phytoplankton.

26. These single celled organisms are covered by plates made of calcium carbonate.

27. Silicoflagellates

28. Because of there small size, very little is known about silicoflagellates except that they can be very important to the primary production in the world’s oceans.