Ribosomes are small dense rounded cell organelle clouds, (1943) sparated as a fraction by ultracentrifugation and named it as microsome. In fact, microsomes refer to particles which get separated from ER. It was rich in ribosomes. On the basis of chemical nature they are described as ribonucleoprotein particles or RNP particles. The plant cell contains many freely distributed sub-units of Golgi apparatus called dictyosome, secreting cellulose and pectin for cell wall formation during cell division. Oxysomes or elementary particles are attached to M face of inner mitochondrial membrane. These are meant for ATP synthesis (phosphorylation) and also for ATP oxidation.