Mitochondria and chloroplast are both membrane-bound. why are they not part of the endomembrane system?

Answer and explanation;This is because neither come from the ER and they are not connected physically or by transport vesicles to organelles of the endomembrane system. Vesicles in the endomembrane system have only single membranes where as mitochondria and chloroplasts have two.Endomembrane System is the collection of membranes inside and around a eukaryotic cell, related either through direct physical contact or by the transfer of membranous vesicles. Contains Plasma Membrane, Nuclear Envelope, ER, Golgi, lysosomes, vacuoles, lysosomes, and vesicles.

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