Question

why are mitochondria and chloroplasts not considered part of the endomembrane system

Answer 1

They are both formerly-autonomous bacteria which have become intimately involved with the eukaryotic cells of plants and animals respectively. They, therefore, contain their own systems of mambranous barriers to their external cytoplasmic environment .

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Answer 2

Hii mate..

As you know that mitochondria and chloroplast have double layer membrane also they are present only in eukaryotes . So as they are found inside the membranous cell they are termed as ENDOMEMBRANE SYSTEM.

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