Why is the euglena said to belong to both the animal as well as the plant kingdom?
Answers
Answer 3:
Plants are multicellular organisms with cellulose cell walls. Depending on the definition, plants may or may not need also to enclose the developing new plant in an embryo (if this definition holds, then green algae are not plants; otherwise, they are).
Animals are multicellular organisms held together by a specific protein called collagen.
Euglena is single-celled, and the cell is enclosed in a semi-rigid protein sheath, not a true cell wall but not a simple cell membrane. Euglena is entirely unicellular, has no collagen and no cellulose, stores energy in paramylon bodies (not starch as plants do).
Euglena is photosynthetic, but the origin of Euglena's chloroplasts is taken *from* a green alga, not directly from cyanobacteria/chloroxybacteria as plants and green algae are.