Question

Red tides in warm coastal water develop due to the abundance of

• A. dinoflagellates
• B. euglenoids
• C. diatoms and desmids
• D. slime moulds.

Answer 1

The correct option is A dinoflagellates

These organisms are mostly marine and photosynthetic. They appear yellow, green, brown, blue or red depending on the main pigments present in their cells. The cell wall has stiff cellulose plates on the outer surface Most of them have two flagella: one lies longitudinally and the other transversely in a furrow between the wall plates. Very often, red dinoflagellates undergo such rapid multiplication that they make the sea appear red.

So the correct option is "dinoflagellates".