Any organell that has membrane outside the organells covering them are called membrane bound organells.Membranes of organells like chloroplast,Golgi, mitochondria,ribosomes,nuclear membrane,cell membrane are made of lipids for protection of the internal matters of the cell and for easy passage of specific vesicles or essential molecules.membranes also have proteins as receptors or channels for.selective transport in to the cell and carbohydrates or proteoglycans for signalling and interaction. Membranes are barriers or.protective layer of the cell.membranes can also act as the site for electron transport chain Example .. like in chloroplast and mitochondria which contains its own membrane with proteins embedded for ETC.chloroplast has its own dna inside the lumen below the membrane allowing specific molecules to enter through Protein channels.
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