Am i doing this right...Its RNA stuff?

Question

Is 36 and 37 correct? and how do i answer #38 am i suppose to find the amino acid sequence for mRNA or tRNA?
http://img256.imageshack.us/img256/7762/mydc00231xb.jpg

Umm is it right or not?

My AIM is DRpopcorny if its more convenient for you...

Answer 1

Yes, you are doing this right.

#38 use the mRNA sequence

Answer 2

No you are wrong.

They give you the DNA sequence

CCA TAC GGC TGC AAC TGC GAC CTG ATT CGC

and say that this could be coding for a gene. Thus it is not the template sequence, but the actual gene sequence and thus the mRNA will have exactly the same sequence with U instead of T:

CCA UAC GGC UGC AAC UGC GAC CUG AUU CGC

***** Parenthesis ****
Note that by convention nucleic acid sequences are always written in the 5'->3' direction.
This means that the DNA sequence they gave you is

5'-CCA TAC GGC TGC AAC TGC GAC CTG ATT CGC-3'

so if the sequence they gave you were the template (and not the coding) you would have

5'-CCA TAC GGC TGC AAC TGC GAC CTG ATT CGC-3'
3'-GGU AUG CCG ACG UUG ACG CUG GAC UAA GCG-5'

and then you have to reverse the RNA in order to be 5'->3'
5'-GCG AAU CAG GUC GCA GUU GCA GCC GUA UGG-3'

*** end of parenthesis ***

tRNAs have to be complementary to the mRNA codons.
Now here is the tricky part. The question is poorly formulated and I can't guess what they are asking for exactly. There is no tRNA strand and you don't translate mRNA into tRNA. Probably they are asking you to find the anticodons

Each tRNA will pair with one codon.
So for the first codon you will have the pairing
5'-CCA-3' (mRNA)
3'-GGU-5' (t-RNA)

but since the correct way to write it is 5'->3' the correct sequence for the tRNA is UGG. Now given the poor formulation of the question I honestly do not know if they are aware of this "detail" or if they would wrongly expect you to answer GGU

2. UAC-> GUA
3. GGC-> GCC
4. UGC-> GCA
5. AAC-> GUU
6. UGC->GCA
7. GAC-> GUC
8. CUG-> CAG
9. AUU-> AAU
10. CGC -> GCG

Translation is always according to the sequence of mRNA so you get the sequence (1 letter code):
P Y G C N C D L I R or in three letter code

Pro Tyr Gly Cys Asn Cys Asp Leu Ile Arg

Answer 3

I know what you are talking about. I did this last year in 7th grade...Amino Acids make proteins using the RNA in cells. mRNA stands for the Messenger Ribonucleic Acid and tRNA is Transfer Ribonucleic Acid. The 2 different RNAs are used for different purposes. Adenines = Thymine or Uracil and Guanine = Cytosine...That is how they are paired up. mRNA carries data from the DNA to bring it to the ribosomes and other sections of the cell. tRNA carries the Amino Acids and does hydrogen bonding to connect the tRNA and mRNA together. I'm so happy I remembered that....lol

Answer 4

you have a t on #4 in trna, amino acids coded by mrna strand

Answer 5

hmmm -this question makes no sense to me - perhaps i'm not reading it correctly, but 'translating from mRNA to tRNA' never happens in cells - in fact, i'm not sure what the term 'translating' even means in this context. tRNAs are coded independently in the genome and their sequence is not related to the mRNA! (except to contain the aa anticodons).

also, tRNAs are not translated into proteins, so #38 must be referring to the mRNA strand.

Good luck - this question seems seriously flawed to me