Question 19:
A DNA or amino acid sequence consisting of residues that most commonly occur at each position in a set of similar sequences are called:
Consensus Sequence DNA Amino Acid
A consensus sequence represents the most frequent residues at each position across aligned DNA or protein sequences. The correct term is option (D).
Correct Answer
(D) Consensus sequence
This sequence emerges from multiple sequence alignments, highlighting conserved motifs critical for function like promoter regions or protein domains.
Key Concept
Bioinformaticians align homologous sequences and select the dominant nucleotide/amino acid per position. High conservation signals evolutionary importance, as in transcription factor binding sites.
Option Analysis
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(A) Classified sequence: Incorrect; no standard term in molecular biology for sequence categorization this way.
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(B) Compound sequence: Incorrect; “compound” refers to chemical mixtures, not sequence analysis.
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(C) Conjugated sequence: Incorrect; conjugation means linked biomolecules (e.g., glycoprotein), unrelated to alignments.
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(D) Consensus sequence: Correct; standard term for the “idealized” representative of aligned sequences.
| Option | Term | Meaning | Status |
|---|---|---|---|
| A | Classified | No specific biology use | Wrong |
| B | Compound | Chemical mixture | Wrong |
| C | Conjugated | Covalently linked molecules | Wrong |
| D | Consensus | Most common residues aligned | Correct |
Exam Preparation Tips
Visualize: Align 5 similar DNA sequences → tally votes per column → consensus = winner (e.g., TATAAT for TATA box). Key for NEET bioinformatics questions.
