Answer: A single tRNA can recognise more than one codon for the same amino acid.
- A How ribosomes physically move stepwise along the mRNA strand
- B A single tRNA can recognise more than one codon for the same amino acid
- C How RNA polymerase correctly selects the appropriate gene promoter
- D How spliceosomes remove introns from precursor hnRNA transcripts
Correct answer: B. A single tRNA can recognise more than one codon for the same amino acid
Explanation: The wobble hypothesis states that the pairing at the third codon position can be flexible, letting one tRNA recognise multiple synonymous codons.
Helicase unwinds the double helix at the replication fork; one new strand (leading) is synthesised continuously toward the fork, while the other (lagging) must be made in short, separate Okazaki fragments because DNA polymerase only adds nucleotides 5'→3'.
Concept context
DNA structure, replication, transcription, translation, the genetic code, and gene regulation (lac operon). The single most important chapter for NEET molecular biology.