ATI TEAS (Test of Essential Academic Skills) Version 7ScienceHard
A patient is diagnosed with a genetic disorder caused by a mutation that results in the production of a non-functional protein. This mutation occurred at the level of DNA, leading to an incorrect mRNA sequence and subsequently an altered amino acid sequence. Which molecular process was directly affected by this mutation, leading to the non-functional protein?
- AReplication
- BTranscription
- CDNA Repair
- DTranslation
Show answer & explanationAnswer & explanation
Correct answer: D. Translation
The question states the mutation leads to 'an incorrect mRNA sequence and subsequently an altered amino acid sequence.' While the mutation originates in DNA (affecting transcription), the direct process that uses the mRNA to build the amino acid chain is translation. An altered amino acid sequence is a direct outcome of errors during translation, guided by faulty mRNA.
Why the other options are wrong
- A. Replication is the process of making copies of DNA; a mutation might occur during replication, but it's not the process *directly* affected by the mutation leading to the final non-functional protein.
- B. Transcription is the process of synthesizing mRNA from a DNA template. An incorrect mRNA sequence implies transcription was affected, but the *subsequent altered amino acid sequence* is directly a result of translation using that faulty mRNA.
- C. DNA repair mechanisms correct mutations; this is a preventative or corrective process, not one that directly leads to protein synthesis.
Central Dogma (Gene Expression)
The fundamental concept that genetic information flows from DNA to RNA to protein, involving the processes of replication, transcription, and translation.
- Replication: DNA makes copies of itself.
- Transcription: DNA is transcribed into mRNA.
- Translation: mRNA is translated into protein (amino acid sequence).
Memory trick: DNA 'R'eplicates, 'T'ranscribes 'T'o 'P'rotein.