Which protists are primarily responsible for red tide events?

Which protists are primarily responsible for red tide events?

• A. Diatoms
• B. Dinoflagellates
• C. Amoebas
• D. Euglenoids

Answer: (B)

Red tides are blooms driven primarily by dinoflagellates, a group of marine protists equipped with two flagella and distinctive cellulose plates. In warm, nutrient-rich, and relatively calm coastal waters they can multiply rapidly and color the water. Some species produce potent toxins that accumulate in shellfish and can cause illness in humans, respiratory irritation, or marine animal die-offs. Diatoms also bloom in the ocean, but their blooms aren’t the typical red tide events and they have different cell structures and pigments. Amoebas and euglenoids may be photosynthetic or heterotrophic, but they aren’t the usual culprits behind red tides. The main factor here is the association of red tides with dinoflagellates.

Red tides are blooms driven primarily by dinoflagellates, a group of marine protists equipped with two flagella and distinctive cellulose plates. In warm, nutrient-rich, and relatively calm coastal waters they can multiply rapidly and color the water. Some species produce potent toxins that accumulate in shellfish and can cause illness in humans, respiratory irritation, or marine animal die-offs. Diatoms also bloom in the ocean, but their blooms aren’t the typical red tide events and they have different cell structures and pigments. Amoebas and euglenoids may be photosynthetic or heterotrophic, but they aren’t the usual culprits behind red tides. The main factor here is the association of red tides with dinoflagellates.