Are other extraterrestrials in Voltron composed of animal cells?
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I know at least one race isn't.
Humans, as well as Galra and many other alien races, originated from animals and thus are comprised of animal cells. The Olkari, however, are not and instead their race evolved from plants thus they are comprised of plant cells and have chlorophyll.
This means while they can eat and drink like other species, in rare occasions such as survival situations they can photosynthesize to sustain themselves. In addition they don't breathe in oxygen but rather the opposite that most plants take in, which is Carbon Dioxide and release oxygen. Furthermore their plant-like origins are probably what gives the Olkari a deep connection to their planet and other organic life forms to the point they can manipulate, intergrate, and utilize almost anything they want, thus making them the universe's greatest engineers.
On another note because humans take in oxygen and release Carbon Dioxide and Olkari do the opposite it's possible Humans and Olkari can have a symbiotic relationship
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