The DNA molecule has a sister sibling, whatever we call it, that is highly similar but not identical. So this fundamental nucleotide part is still largely relevant, but if you make that one small charge and swap an OH group to an H group, you get a almost completely different molecule. It's of course not completely different. The building blocks are virtually the same, but this changes the stability and hydrogen bonding patterns in the molecule. So instead of having a stable double helix, we're going to end up with something that is not a double helix. You actually change the basis too. Instead of having A, G, C and T, that thymine is replaced for another molecule called Uracil, not a base called Uracil. The reason for that is actually pretty smart in evolution, so that the cited scene base can actually be degraded under some conditions to form Uracil. That would be a disaster in DNA, right? Because then there are two molecules and if cited scene in some conditions would be degraded, you could end up with literally changing the code description in the book. So having thymine in DNA instead of Uracil means that we have a different description in DNA so that the DNA in RNA doesn't matter, because the RNA is just transient and the RNA is normally never used to produce new, the next generations, genetic code. So DNA and RNA have slightly different roles and evolution have then adapted them to this to have basis optimized for the different usages. As I mentioned, RNA is a single-stranded chain. It's also much floppier. It is not at all a stable as DNA, where DNA can be stable for under some conditions for thousands or even tens of thousands of years. RNA will degrade in mere hours in the lab. We typically have to put RNA on ice when we work with it. DNA will actually degrade too, and that's the reason why radiation damage, for instance, will damage your genetic material in DNA. But due to the complementarity of the base pairs under most conditions, your cells can repair that, as long as the damage is not too severe. But of course, as we get older and everything, this becomes more fragile and then there are some points that will lead to tumors. There are a few different types of RNAs that I'm going to take you through and let's see what they do.