Read the given descriptions of two organisms, X and Y: Organism X is marine and photosynthetic, appearing yellow, green, brown, blue, or red depending on the main pigments present in its cells. Organism Y is found in stagnant water, photosynthesises in the presence of sunlight, but predates on smaller organisms when deprived of sunlight. Select the correct statement regarding the cell wall or outer covering of organi

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Based on the given descriptions, organism X is a dinoflagellate because they are mostly marine, photosynthetic, and appear in various colours depending on their pigments. Organism Y is a euglenoid because they are found in stagnant water and exhibit mixotrophic nutrition (photosynthetic in light, heterotrophic in dark). Dinoflagellates (X) have stiff cellulose plates on the outer surface of their cell wall. Euglenoids (Y) lack a cell wall; instead, they have a protein-rich layer called a pellicle which makes their