It would not be plants, even though it has cell walls. They are not made of chitin. Plants are also not heterotrophic.
Fungi, however, decompose other matter, and have cell walls made of chitin. This would fit the description.
Human and the natural ones can change the ecosystem
You can do golden rice. It was genetically modified to produce beta carotene, which rice does not usually have. When metabolized by the body beta carotene is turned to vitamin A which is essential to human vision, immune systems, and healthier skin
Answer: the study of living organisms, divided into many specialized fields that cover their morphology, physiology, anatomy, behavior, origin, and distribution.
or
the physiology, behavior, and other qualities of a particular organism or class of organisms.
and
the plants and animals of a particular area
