The red despot on the euglena is important for detecting light for photosynthesis and filters the sunlight to only allow certain wavelengths of light to a structure at the base of the flagellum
An Euglena is a protozoan. It has an single cell which makes it a unicellular organism. It is also has a well defined nucleus with membrane bound organelles which makes the Euglena eukaryotic in nature.
An Euglena possesses both human and plant like traits. Its human trait is that an Euglena moves with the aid of a flagella. Its plant like trait is that an Euglena has chloroplast present as one of its membrane bound organelles which its uses for photosynthesis.
Due to the presence of animal and plant like traits in an Euglena, and Euglena is both autotrophic and heterotrophic in nature.
One of the organelles present in the Euglena is its eyespot. This is a very important organelle because the Euglena uses the eyespot to detect sunlight for the process of photosynthesis. The chloroplast then traps this detected light for photosynthesis.
The excretory system is most likely to respond when an animal is thirsty in this way: B. by retaining body fluids. Because the body doesn't get enough fluids to not be thirsty anymore, it retains whatever fluids it already has in it until the thirst is satiated.
