The student asked for help understanding how to take a DNA sequence, transcribe it to mRNA and then translate it to amino acids. Detailed information is given to explain the steps one needs to take in order to accomplish both tasks. The assignment posted also asked about mutations, so an explanation of mutations is also provided. Finally, the properties of amino acids are briefly discussed.
Thank you for contacting BrainMass to explain transcription and translation to you!
OK, so the first thing you need to know is the DNA base pair rules: T (Thymine) pairs with A (Adenine) and G (Guanine) pairs with C (Cytosine). This happens because of the hydrogen bonding properties of each - C and G can each form three hydrogen bonds and A and T can only form two. A more detailed explanation as well as a picture of the bonding can be found here: http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/B/BasePairing.html
When you transcribe RNA from DNA, similar base pairing rules apply: C and G pair up; the difference is RNA does not have "T" - instead it has a "U" (Uracil). So when transcribing DNA to RNA, T pairs with A, but A pairs with U!!
Knowing that, we can start filling in the table in the excel sheet:
The first cell in your assignment says TAC; following the rules above, T pairs with A; A pairs with U (remember, we are making RNA!!) and C pairs with G. So the first RNA group is AUG.
The next group is AAA. Since A pairs with U, the next transcription gives us UUU.
CAT is the third row down; C pairs with G; A pairs with U and T pairs with A = GUA.
It is often easier to see if you write them in two rows like this:
DNA: TAC AAA CAT
RNA: AUG UUU GUA
Since BrainMass is not a homework completion service, I will let you practice the rest of the transcription on your own and move on to translation.
Translation takes the RNA sequence and changes it (translates it) to amino acids. This happens on the ribosome - Figures ...