in the earlier video we were looking at the relationship between DNA rnas and amino acids and how the cell uses all these molecules in order to make a polypeptide and that process is known as protein synthesis right so but what we have to understand here is proteins synthesis is actually split into two different processes the first process of protein synthesis is transcription where the gene is transcribed or copied to produce the MRNA and the second part of protein synthesis is known as translation where the MRNA goes to the ribosome and then the Tierney carries the amino acids to the ribosome and a polypeptide is synthesized so in this video we are going to be looking at transcription first so remember transcription is just when the gene is transcribed or copied to produce the MRNA you see in the process of transcription what we have to understand first is the gene has to be copied to produce mRNA now when I Circle the gene which is found in the DNA the gene is made up of well it's basically DNA right and it's double stranded but the MRNA is single stranded so here's where it becomes a bit peculiar how is it that something double stranded produces something single standard which is the MRNA so we have to understand that process of transcription in detail so without wasting any time when transcription happens only the section of the gene unwinds Unlike DNA replication where the entire DNA has to unwind right but in transcription only that particular section where I've highlighted has to unwind and the bases are then exposed now fourth transcription only one strand which I'm referring to as the template slant is required it does not involve both the strands so I finally I've labeled the template strand I've also labeled the none templates plan template meaning to say it's required for transcription none template meaning to say it is not going to be required for transcription like that now I'm going to zoom in and only on the templates line and put out a base sequence so the base sequence of the gene in the templates then can be there can be many different types of Base sequences you don't have to memorize the base sequence by the way some of some of my students oh my god do I have to do this do I have to memorize the entire sequence no that's ridiculous okay B sequences are not to be memorized I mean unless you're a masochist then go for it but you don't have to so I'm drawing out the base sequence over here as you can see a Tac GGC TT c a a g cgc GCT and act all right um when the template stands basic when the base sequences are exposed what needs to happen is RNA nucleotides will go towards the template strength and form complementary base spellings with them so remember when RNA nucleotides form complementary base sequences RNA nucleotide a will pair up with the template T but if the template has a base known as a the RNA nucleotide has to be uracil or U because remember RNA nucleotides do not have thymine they have uracil instead so if the DNA has a base sequence of TAC the RNA nucleotide sequences will have to be a u g that's how it works and they form the hydrogen bonds between each other that's what happens like that and I'm just writing on all the RNA nucleotides so you can just compare and see if I did it correctly all right so what happens then is they form hydrogen bonds between the RNA nucleotides and the templates lens and once that happens another enzyme comes along and once that happens an enzyme comes along and the name of this enzyme is called RNA polymerase remember in DNA replication we had to use an enzyme called DNA polymerase to join DNA nucleotides together so obviously if you want to join RNA nucleotides together you have to use something called RNA polymerase it's in the name it polymerizes or joins together along the nucleotides so the RNA polymerase will basically move along the nucleotides and as they move they join the other nucleotides from a five Prime to three prime Direction This is how you get the MRNA and the MRNA detaches from the template Strand and that's how you get the MRNA basically okay and what then happens to the DNA the DNA just basically reforms and it winds back up together that's basically the process of transcription in detail