Differences in the density of water can<span> also cause </span>currents<span> to form and move. Density is </span>affected<span> by temperature and </span>salinity. Cold water or water with dissolvedsalts<span> (higher </span>salinity<span>) is denser than warm water or water without dissolved </span><span>salts.</span>
DNA, or deoxyribonucleic acid, is a long chain molecule that plays a central role in life on earth. The information encoded in strands of DNA controls the genetic makeup of organisms. The DNA molecule has a backbone of sugars and phosphate groups off of which hang simpler units called nucleotide bases.
The DNA is a double-stranded molecule that has a long chain of nucleotides. The RNA is a single-stranded molecule which has a shorter chain of nucleotides. DNA replicates on its own, it is self-replicating. RNA does not replicate on its own.
