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Stuck on a DNA question

okay so I have some biology HW and I'm just really stuck on this question. I don't know if I'm over thinking it but idk

the Question is:
The sequence of bases on a piece of mRNA was:

mRNA AUGGUAGUGCAUCUUUGA

What would have been the sequence of bases on the,
1 - DNA template strand
2 -on the non-coding cDNA strand
3-the sequence of tRNA anticodons
4-the final amino acid sequence

It also comes with a table of what a triploid of bases would be. IDK how to explain it.
Attachment not found



Normally I would just leave it blank and fill it in in class once I understand it, but my new teacher has a rule that if you leave a question blank, you get minus the marks, so if I leave it blank ill get -4 marks. like its good to catch out the lazy students but he's not a very approachable guy and tends to set work for the next day so it's hard to talk to him if I have a problem. Because of this stupid rule, I have been getting minus marks in HW tests and now I'm just desperate not to do that again.
(edited 6 years ago)
Original post by atomicplaty
okay so i have some biology hw and i'm just really stuck on this question. I don't know if i'm over thinking it but idk

the question is:
The sequence of bases on a piece of mrna was:

Mrna augguagugcaucuuuga

what would have been the sequence of bases on the,
1 - dna template strand
2 -on the non-coding cdna strand
3-the sequence of trna anticodons
4-the final amino acid sequence

it also comes with a table of what a triploid of bases would be. Idk how to explain it.
Attachment not found



normally i would just leave it blank and fill it in in class once i understand it, but my new teacher has a rule that if you leave a question blank, you get minus the marks, so if i leave it blank ill get -4 marks. Like its good to catch out the lazy students but he's not a very approachable guy and tends to set work for the next day so it's hard to talk to him if i have a problem. Because of this stupid rule, i have been getting minus marks in hw tests and now i'm just desperate not to do that again.


2/3)taccatcatgtagaaact
(edited 6 years ago)
1) ATGGTAGTGCATCTTTGA (because the whole reason the coding DNA strand is called the 'template strand' is that the mRNA sequence is identical to it, other than the Thymine in the case of mRNA which is swapped for Uracil)
2) TACCATCACGTAGAAACT (the non-coding strand must be complementary to the coding strand)
3) TACCATCACGTAGAAACT (the tRNA sequence must be complementary to the mRNA strand)
4) Unsure but if I had to guess I'd say TGA...
(edited 6 years ago)
Original post by RED
1) taccatcatgtagaaact


This is a common mistake to make - the sequence you've given is that of the non-coding DNA strand. You need to rememeber that mRNA and the coding DNA strand (template strand as OP has called it) have the same sequence other than the Uracilm which is replaced by Thymine in the DNA coding strand sequence.
It has 6 triploids
Tac
Cat
Cat
Gta
Gaa
Act

I believe
Original post by Wolfram Alpha
This is a common mistake to make - the sequence you've given is that of the non-coding DNA strand. You need to rememeber that mRNA and the coding DNA strand (template strand as OP has called it) have the same sequence other than the Uracilm which is replaced by Thymine in the DNA coding strand sequence.


Oh yeah meant to put it for 2 and 3 sos 😂
omg thank you for the quick replies

tbh i originally put the same as "RED" for no.1 but wasn't 100% so thanks for explaining it Wolfram Alpha

thank you both!!!!!!!!
Original post by AtomicPlaty
omg thank you for the quick replies

tbh i originally put the same as "RED" for no.1 but wasn't 100% so thanks for explaining it Wolfram Alpha

thank you both!!!!!!!!


No problem- you're doing a-level right / AS?
The others have already been answered but for Q4 I think they want you to translate the mRNA into amino acid using the table you're given.

You should get:
DNA: AUG-GUA-GUG-CAU-CUU-UGA
which translates to
AA: Start -Val-Val-His-Leu- Stop
- yeah I'm in my second year :biggrin:

- thanks lillydew
Original post by AtomicPlaty
- yeah I'm in my second year :biggrin:

- thanks lillydew


I'm in first year but our teacher hasn't covered it yet I just tried using what I already knew from GCSE and some slight reading ahead 😂😊😎
oh gawd yes do that. i have so manny regrets from first year about not really revising anything at all.
tbf im wasnt good at biology in the first place and everyone in my class are like doctor material so i got behind real quick because of the fast pace.
good luck with everything though, with the way your already handling the subject, your gonna do well :wink:
Original post by AtomicPlaty
okay so I have some biology HW and I'm just really stuck on this question. I don't know if I'm over thinking it but idk

the Question is:
The sequence of bases on a piece of mRNA was:

mRNA AUGGUAGUGCAUCUUUGA

What would have been the sequence of bases on the,
1 - DNA template strand
2 -on the non-coding cDNA strand
3-the sequence of tRNA anticodons
4-the final amino acid sequence

It also comes with a table of what a triploid of bases would be. IDK how to explain it.
Attachment not found



Normally I would just leave it blank and fill it in in class once I understand it, but my new teacher has a rule that if you leave a question blank, you get minus the marks, so if I leave it blank ill get -4 marks. like its good to catch out the lazy students but he's not a very approachable guy and tends to set work for the next day so it's hard to talk to him if I have a problem. Because of this stupid rule, I have been getting minus marks in HW tests and now I'm just desperate not to do that again.


Original post by Wolfram Alpha
This is a common mistake to make - the sequence you've given is that of the non-coding DNA strand. You need to rememeber that mRNA and the coding DNA strand (template strand as OP has called it) have the same sequence other than the Uracilm which is replaced by Thymine in the DNA coding strand sequence.


The coding strand (or sense strand) is not the same as the template strand. The template strand refers to the non-coding strand (or antisense strand) which RNA polymerase II uses as a template to synthesise a complementary mRNA strand; the coding strand is exactly the same as the mRNA strand (except it contains thymine instead of uracil).
Original post by Jpw1097
The coding strand (or sense strand) is not the same as the template strand. The template strand refers to the non-coding strand (or antisense strand) which RNA polymerase II uses as a template to synthesise a complementary mRNA strand; the coding strand is exactly the same as the mRNA strand (except it contains thymine instead of uracil).


Ahhh I see, I had read somewhere that coding strand and template strand are the same thing but thanks for the calrification :smile:

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