A prokaryotic cell is a simple, single-celled (unicellular) organism that lacks a nucleus, or any other membrane-bound organelle.In prokaryotes, the DNA (chromosome) is in contact with the cellular cytoplasm and is not in a housed membrane-bound nucleus. ... Throughout the course of evolution, organelles such as mitochondria and chloroplasts (a form of plastid) may have arisen from engulfed prokaryotes.
The sugar found in RNA is ribose, whereas the sugar found in DNA is deoxyribose, both of which are 5-carbon sugars. Both types of sugars are important components of nucleotides. The sugars which can be found in nucleic acid are pentose sugars, part of what makes up DNA
The cell membrane is a lipid bilayer that prevents that passage of water and ions. This allows cells to maintain a higher concentration of sodium ions out the outside of the cell.
The theory of evolution tells us that favorable traits will become dominant in a population over time. This means that those of a species who are "unfit" will eventually die out.
