The Difference Between DNA & RNA

Every living cell in our bodies contains two genetic material compounds called Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA), which are responsible for the reading and storing of our genetic information, our cell production, and the creation of proteins responsible for life. Although both of these acids contain genetic material and are linear polymers consisting of sugars, phosphates, and bases, they do have some key distinctions and differences between the two. In this article, we will explore these differences to gain a better understanding of how these two acids work and fulfill their essential roles.

What Are The Functions of DNA & RNA?

When we take a look at DNA or Deoxyribonucleic acid, we see that it has two functions. In the short term, it encodes all genetic information and acts like a blueprint from which genetic life is created. In the long term, DNA acts as a storage device, similar to a biological flash drive that allows the blueprint to be passed down from one generation to the next. The function of RNA is to read and decode DNA, in a multi-step process that follows the following steps:

  • Messenger RNA (mRNA) copies genetic code portions using a transcription process and transports these copies to ribosomes, which are cellular factories that produce proteins from this copied code.
  • Transfer RNA (tRNA) brings amino acids, which are the basic protein building blocks of our cells, to the cellular factories as requested by the coded instructions of the Messenger RNA. This process is called translation and is responsible for protein building.
  • Ribosomal RNA (rRNA) is the main component that makes up the ribosome factory, and without it, we would not get protein production at all.

Now that we’ve gone over the different functions of DNA and RNA, let’s take a look at the main differences between the structure, length, genetic make-up, location, and reactivity.

What Are The Differences Between Structure, Length, Location, and Reactivity?

Both DNA and RNA are made up of subunits called nucleotides, but DNA consists of two strands that are arranged in a double helix formation, whereas, RNA is made up of only one strand. The nucleotides of DNA contain 5-carbon sugar molecules, a nitrogenous base, and a phosphate, while RNA has shorter strands and will sometimes temporarily form a secondary helix structure intermittently. In terms of the length of the strands, a single chromosome may be several centimeters in length when unraveled while a large RNA molecule may only be a few thousand base pairs in length.

With regards to the genetic make-up of DNA and RNA, both contain sugars but in DNA the sugar is deoxyribose which contains one less hydroxyl group than RNA, and RNA contains ribose sugar molecules that do not have the hydroxyl modifications of deoxyribose. The bases of each contain Adenine, Guanine, and Cytosine, but RNA contains Uracil rather than Thymine.

When we take a look at the stability of DNA, we see that is is more stable than RNA as it contains one less oxygen-containing hydroxyl group. RNA tends to be more reactive than DNA because of its helical groove, which is more easily attacked by enzymes and thus prone to unstable conditions. On the other hand, RNA is more resistant to damage done by UV light while DNA is quite vulnerable to it. Finally, DNA can be found primarily in the nucleus with a small amount found in the mitochondria, whereas, RNA forms in the nucleolus and moves on to specialized regions within the cytoplasm.