The question below consists of a set of labelled sentences. Out of the four options given, select the most logical order of the sentences to form a coherent paragraph.

P. The genetic material of bacteria is contained in a single loop of deoxyribonucleic acid (DNA).

Q. Notably, some bacteria have an extra circle of genetic material known as the plasmid.

R. Bacteria are unicellular organisms with a much simpler cell structure than other organisms.

S. A key difference between bacteria and other biological organisms is that they have no membrane -bound organelles and a lack of nucleus.