Dat Destroyer 2017 Bio #233

[Veni vidi vicii]

A particular triplet of bases in a DNA coding sequence is GGA. The anticodon on the tRNA that binds the mRNA codon is ___? GGA is the answer.

The tRNA anticodon is the same as the DNA template strand and NOT the coding strand.
So if the coding strand is GGA, then template strand is CCT, so mRNA is GGA, and tRNA would be CCU right?
@orgoman22

Any help?

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[DAT Destroyer]

A particular triplet of bases in a DNA coding sequence is GGA. The anticodon on the tRNA that binds the mRNA codon is ___? GGA is the answer.

The tRNA anticodon is the same as the DNA template strand and NOT the coding strand.
So if the coding strand is GGA, then template strand is CCT, so mRNA is GGA, and tRNA would be CCU right?
@orgoman22

Any help?

Yes, if you are referring to tRNA it should have the same sequence as the template strand

 

[Veni vidi vicii]

Yes, if you are referring to tRNA it should have the same sequence as the template strand

So why is the answer GGA? The question is asking about the anticodon on tRNA so it would be CCU, right?

 

[bigboikhoa]

The DNA template is GGA. Thinking about the central dogma, its transcription, then translation. First with transcription, you make an mRNA using the template DNA strand. This will yield an mRNA that reads CCU. Then you need to move onto translation. The tRNA anticodon will bind onto this mRNA CCU. Therefore, the anticodon of the tRNA has to be GGA.

 

[Veni vidi vicii]

If the coding sequence is GGA I would assume the coding strand, not the template strand is GGA

 

[bigboikhoa]

I get what you are asking now, yeah I misread. If the coding sequence is GGA, the template strand should be CCU. Then the mRNA created should be GGA and the anticodon of the tRNA should be CCU. Your reasoning seems correct to me.

 

[DAT Destroyer]

Ok. The question presumes the coding sequence located on the template strand. Therefore, mRNA sequence should be CCU and then the tRNA anticodon sequence should be complementary to that, which is GGA.
Hope this helps.

 

[lwergod]

coding=! template strand

5"coding 3"
3" template 5"
5" mRNA 3'

notice coding is the same as the mRNA, with the exception of uracil replacing thymine.

 

[u_stepped_on_mi_to_sis]

Is the coding sequence always presumed to be on the template strand? I would think it would be synonymous with the coding strand.

yes! always, always, always (for DAT purposes at least)..

DNA sequence: GGA
mRNA sequence: CCU
anticodon: GGA