DNA vs. RNA

The ultimate battle of the nucleic acids in pixels, described!

Hey guys! I was researching a bit about molecular biology lately, and wondered, what’s the difference between DNA and RNA? These nucleic acids will be taken through a couple of different stages to see the bigger picture; the answer to my question. First, we’ll take a look at DNA and RNA’s monomers; nucleotides. Then we’ll look at where they are found in a cell. Finally, we can conclude with their roles in helping cells anyways! So let’s dive in!

The monomer of both DNA & RNA are nucleotides: and there are three main building blocks of nucleotides. First, there are three phosphates and some other atoms, or three phosphate groups. PO₄³⁻ is the formula for one phosphate group, and yes, it’s an negatively charged ion. On to building block number two!

Then there’s a nitrogeneous base. There are five different kinds that you may recall; Adenine, Thymine, Cytosine, Guanine, and finally, Uracil. A, T, C, G, and U! A always goes with T in DNA, and C always goes with G! But what about U? The uracil is in fact never found in DNA! The U is like the T, except in RNA. So you also won’t find thymine in RNA! Let’s jot that down, because it’s our first major difference!

But I said there were three building blocks, right? There are! The final building block of a nucleotide is a pentose sugar. But again, we can find a difference! In DNA, the pentose sugar is called deoxyribose, hence the full name deoxyribonucleic acid. With this knowledge, can you guess what the pentose sugar in RNA is? That’s right; it’s ribose! The full name of RNA is ribonucleic acid, so that wasn’t a tough one.

But wait. There’s another feature can be described as a major difference between RNA and DNA! It’s that DNA is a double helix, so it’s double stranded! Meanwhile, RNA is single stranded. Of course, there are exceptions, there are always exceptions in biology, but generally you can remember this base rule: DNA has two strands while fellow RNA has one. We can move on to where DNA and RNA are found now!

In eukaryotes, DNA is always found in the nucleus. Prokaryotes? Well, they don’t have a nucleus. But RNA can be found in lotsa places! Inside the nucleus, in the ribosomes, in the cytoplasm… the list can go on. So, using eukaryotes for demonstration, DNA is found in the nucleus, while RNA is found inside and outside the nucleus. Finally, let’s talk about their roles in cell function.

DNA is like the big boss for cells. It codes for every gene in your entire body. Make a few tweaks, and your have three eyes. A few more, and you have six fingers. Every protein is controlled by your DNA because it matched up with the amino acid to create polypeptide chains that have different interactions with different molecules… protein synthesis & folding are topics for seperate posts! But in general, your DNA is the blueprint for everything going on in your body.

RNA is like the ‘doer,’ the one that actually follows the blueprint & carries out commands. How? Again, that’s for a different post. But RNA makes up your ribosomes, clicks together with amino acids, creates peptide bonds between them, and makes primary structures for proteins. Then, in the endoplasmic reticulum, the protein can be folded into it’s full potential and become a structural or functional protein. These are the traits you can physically see, like your skin & eye color, or if you have hitchhiker’s thumb. And that’s the final difference!

Let’s come to a conclusion. DNA and RNA are both vital to your cells, but have many differences. First and foremost, the structure is different. The kinds of nitrogeneous bases and pentose sugars found in DNA & RNA’s nucleotides are different, and the structures are also seperate, with a few exceptions. The DNA is only found in the nucleus of eukaryotic cells, while RNA is found in and outside. Finally, DNA is like the blueprint for the genes in your body; once it is replicated, you have a DNA template strand. Meanwhile, RNA is like the doer, or the one that follow the DNA’s instructions.

That might have been a mouthful, and quite a bit to remember, but molecular biology is very fun, and once you’ve learned these basics, you can go on to study protein synthesis, the conversion of nucleic acids into useful proteins, or other aspects of biology. This is just the base for many, many more mouthfuls of information to come. Thanks, and I’ll see you next time!