Question

What color does the outside stigma of Euglena have?

1) Green
2) Red
3) Blue
4) Yellow
5) Cannot be determined

Answer 1

The outside stigma of Euglena is red, which they use to sense light and perform photosynthesis. Species like Euglena sanguinea can color entire ponds red.

Step-by-step explanation:

The color of the outside stigma, or eyespot, of Euglena is red. The stigma is used by the Euglena to sense light, guiding them toward light sources. This red eyespot is crucial for conducting photosynthesis, as it helps the organism to orient relative to the light. Interestingly, certain species of Euglena, such as Euglena sanguinea, can give a pond a red coloration, though this is due to the mass presence of the organisms rather than the color of a single stigma.