hey everybody dr. Oh here so now we've transcribed our DNA in the RNA now it's time to translate it into protein so let's go ahead and dive in so just like transcription we're gonna have the three steps initiation elongation and termination we are we are translating our RNA which is in the nucleic acid language into a protein which is in the amino acid language that's why it's called translation so the three key players you see there at the top when I say are an RNA what I actually mean is mRNA that's gonna be the message that's going to be translated the other key players are our RNA or ribosomal RNA the ribosome has that large and small subunit the ribosomes in our cells are called 80s ribosomes the ribosomes and bacteria are called 70s ribosomes so the message is messenger RNA the location where translation is going to occur is the ribosome or our RNA and then tRNA transfer RNA is going to be the actual translator so we have the message mRNA the translator tRNA and the location where translation is going to occur our RNA or the ribosome there are different types of ribosomes free ribosomes inside ourselves make proteins it'll stay in those cells fixed ribosomes are part of the rough endoplasmic reticulum and they're gonna make proteins that leave the cell I cover that in the video on the ribosomes okay I think we are ready to get started so I just I wanted to show you the transfer RNAs how they work there should be 61 of these each one can read a three-letter sequence and then bring with it one of the amino acids obvious there's not 61 amino acid so I'll show you the unit code in just a minute we only need we only need to be able to bring 20 unique amino acids into a protein as we build it so the steps initiation is going to begin at what's called the start codon which is always Aug so a a codon is a triplet of bases or three bases on RNA that are converted or translated into the amino acid language so the start codon is called Aug so you have the start codon is where initiation takes place elongation the messenger RNA is read three letters at a time and amino acids are brought notice that protein or polypeptide chain is being lengthened every time a new trans for RNA comes on reads the next three letters it leaves an amino acid behind which is bound together by peptide bond and that protein is going to continue to get longer and longer until termination termination is going to be when the ribosome runs into one of your three stop codons so it goes start codon elongation to the stop codon just like with transcription it was promoter sequence of DNA - terminator sequence this is start codon to stop codon let me show you the genetic code so you see the start codon down there Aug and this is the same genetic code that all living things you use so Aug it codes from a thiamine so that's gonna be your start codon then you have so 61 of these are called sense codons because they can be read then so cuu codes for leucine CCU codes for prolene and then you're gonna bump into one of your three stop codons at the end also known as nonsense codons stop codons are fine but I like to call them nonsense codons because it's not that this machinery can read it as a stop sign it just can't read it at all it's nonsense to it which is why translation stops so your three stop codons are you a a UAG and UGA so you have your 61 cents codons including the start codon and your three nonsense codons you'll notice though so why we have 64 of these codons and only 20 amino acids that's because if that's because your codons are triplets if there were only you know two base pairs in a codon we wouldn't have enough slots to have all 20 amino acids so instead you'll see that CCU cccc CA and CCG all code for prolene so some of these amino acids have four separate codons that will code for them some only have one but there's some variation there we'll talk when we get to mutations about how this is something called degeneracy the fact that CCU and CCC both code for the same amino acid means that there could even be a mutation that could convert CCU to CCC and nothing wouldn't matter because you'd have you'd still have the right amino acid and the right in the right spot there alright so that's gonna be translation I hope this helps have one of the day be blessed