Question

A colourless dinoflagellate, which is also classified as protozoa is

• A. Euglena
• B. Ceratium
• C. Noctiluca
• D. Gonyaulax

Answer 1

The correct option is C Noctiluca

Noctiuca, the night light, is a colourless dinoflagellate which exhibits holozoic nutrition and exhibits bioluminescence. Dinoflagellates are characterized by presence of pigment luciferin which is acted upon by the enzyme luciferase causing production of light without any heat; the bioluminescence. Absence of armoured cell wall, a characteristic feature of dinoflagellates, and presence of pellicle make them a protozoan. Option C is correct. Euglena is a eugneloid; a unicellular biflagellated alga that exhibits eugneloid movement, presence of histone proteins makes it distinct from dinoflagellates. Option A is incorrect. Ceratium is a dinoflagellate with characterstic armoured cellulosic cell wall and typical golden brown color; option B is incorrect. Gonyaulax is a red dinoflagellates; option D is incorrect. Thus, the correct answer is option C.