Question

Mostly marine, photosynthetic and biflagellate organisms are

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

Answer 1

The correct option is D

Dinoflagellates

The correct option is option D.

Explanation of the correct option:

1. Dinoflagellates are photosynthetic, mostly found in marine water.
2. Most organisms of this group are motile and flagellate. Two flagella are found in these normally.
3. So, these are also called biflagellate.

Explanation of the incorrect options:

Option A:

1. Desmids are mostly found in marine water.
2. These are also photosynthetic algae.
3. Do not have flagella.

Option B:

1. Diatoms are mostly found in marine water.
2. These are also photosynthetic but lack flagella.
3. Flagella are only found during the reproductive stage.

Option D:

1. Euglenoids bear two flagella.
2. These are mixotrophic and can perform photosynthesis.
3. These can be found in marine water but are mostly found in freshwater.

Final answer: Mostly marine, photosynthetic and biflagellate organisms are dinoflagellates.