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Need some help on a gene technology question AQA A level

https://pmt.physicsandmathstutor.com/download/Biology/A-level/Topic-Qs/AQA/8-Control-of-Gene-Expression/Set-C/8.4%20DNA%20probe%20and%20Gel%20Electrophoresis%20QP.pdf

https://pmt.physicsandmathstutor.com/download/Biology/A-level/Topic-Qs/AQA/8-Control-of-Gene-Expression/Set-C/8.4%20DNA%20probe%20and%20Gel%20Electrophoresis%20MS.pdf

The question is 1b and it asks how anti sense gene would reduce the expression of the SUT1 gene so i said maybe it produces an enzyme which hydrolyses the sucrose co-transporter protein the SUT1 gene makes but i was completely wrong and the actual answer wanted you to talk about how the anti sense gene binds to the sense gene and forms double stranded MRNA.

I just want to know if the question provided hints for this answer or how my thought process was wrong. I appreciate any help
Reply 1
Hey , soo i read the question i think one of the hints is that it says ANTIsense SUT1 MRNA - The word anti just clicks to you that its opposite to the original sense SUT 1 and since opposite base sequences = complementary which then you can map out that double stranded MRNA which means that it can no longer bind to Trna to form a protein (as it’s not single stranded) soo its not translated - does that make sense?
(ps this was a slightly difficult question as i can see why you mentioned it makes a enzyme but just read the question and 1 hint or two will be there for sure)
Original post by 43Explosion
https://pmt.physicsandmathstutor.com/download/Biology/A-level/Topic-Qs/AQA/8-Control-of-Gene-Expression/Set-C/8.4%20DNA%20probe%20and%20Gel%20Electrophoresis%20QP.pdf
https://pmt.physicsandmathstutor.com/download/Biology/A-level/Topic-Qs/AQA/8-Control-of-Gene-Expression/Set-C/8.4%20DNA%20probe%20and%20Gel%20Electrophoresis%20MS.pdf
The question is 1b and it asks how anti sense gene would reduce the expression of the SUT1 gene so i said maybe it produces an enzyme which hydrolyses the sucrose co-transporter protein the SUT1 gene makes but i was completely wrong and the actual answer wanted you to talk about how the anti sense gene binds to the sense gene and forms double stranded MRNA.
I just want to know if the question provided hints for this answer or how my thought process was wrong. I appreciate any help

Hi nitroglycerine event [sorry| 😄,

One of the tactics I train my students on when improving exam technique is to teach them to v quickly try to work out which specific part of the syllabus the Q is testing your knowledge of.

In this Q, you need to realize that the mention of SUT1 is simpy a ploy to distract/confuse you - as far as I know SUT1 is not even in AQA syllabus hence the Q explains its function.
Crucially, if you had grasped the fact that this Q is testing your knowledge of transcription and translation, you would probably have worked out the correct answer:undefined:.

Good luck in imminent exams!

M [specialist biology tutor]
Reply 3
Original post by hhhhs2002
Hey , soo i read the question i think one of the hints is that it says ANTIsense SUT1 MRNA - The word anti just clicks to you that its opposite to the original sense SUT 1 and since opposite base sequences = complementary which then you can map out that double stranded MRNA which means that it can no longer bind to Trna to form a protein (as it’s not single stranded) soo its not translated - does that make sense?
(ps this was a slightly difficult question as i can see why you mentioned it makes a enzyme but just read the question and 1 hint or two will be there for sure)

I appreciate the help a lot and it makes a lot more sense now. I'm bad at finding hints in questions but am working on it for the exam.
Reply 4
Original post by macpatgh-Sheldon
Hi nitroglycerine event [sorry| 😄,
One of the tactics I train my students on when improving exam technique is to teach them to v quickly try to work out which specific part of the syllabus the Q is testing your knowledge of.
In this Q, you need to realize that the mention of SUT1 is simpy a ploy to distract/confuse you - as far as I know SUT1 is not even in AQA syllabus hence the Q explains its function.
Crucially, if you had grasped the fact that this Q is testing your knowledge of transcription and translation, you would probably have worked out the correct answer:undefined:.
Good luck in imminent exams!
M [specialist biology tutor]
I have a hard time finding out what the questions actually wants from me a lot of the time but am working on improving this. Thank you for the help!

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