The cytoplasm

Around 80 percent of the cytoplasm is water; lipid,  the other fifth is protein, nucleic acid, carbohydrate, inorganic ions and other low molecular weight compounds. The cytoplasm is the medium for enzyme activity and contains the ribosomes. Other subcellular structures which may be present are inclusion bodies storage granules made of compounds like as the membrane-associated cytoplasmic or poly-b-hydroxybutyrate polyphosphate.

Figure . Bacterial and Archaeal cell membranes. The Bacterial membrane (a) is made up of A lipid bilayer, while the Archaeal membrane (b) has transmembrane phospholipids as well as some regions of bilayer.  The phospholipids of Archaea are also branched.

magnetosomes and carboxysomes. The magnetosome is established in magnetotactic bacteria such as Magnetospirillum and is thought to play some role in biomineralization.

Although Archaea and Bacteria lack true organelles some species have   developed membranous configurations to aid some biochemical procedure.Cyanobacteria, such as Anabaena carry out oxygenic photosynthesis at thylakoid membranes that are lined with phycobilisomes. The green sulfur bacteria such as Chlorobium perform anoxygenic photosynthesis in chlorosomes. Unlike the thylakoid membranes these are separate from the cell membrane. Another technique of anoxygenic photosynthesis uses spherical or lamellar systems attached to the cell membrane example for purple Bacteria such as Rhodopseudomonas.

The main drawback in the study of the fine structure of prokaryotes is the technique used to view such small objects. Electron microscopy which is also known as EM has provided us with many of the details given here and in other texts, but the harsh methods used to fix and develop the samples are prone to generation of artifacts. Example for of this is the mesosome a small vesicle seen in various EM preparations often seen budding from the cell membrane. It is possible that these have one of the proposed roles in cell division cell wall synthesis or chromosome resolution but it seems more likely that mesosomes are created during the EM drying and fixation process.