AI-generated explanation. Check against your textbook.
Explanation:
Correct option: 2. In bacteria, transcription termination can be Rho-dependent, where the Rho factor binds to the RNA and helps terminate transcription. This mechanism is described in NCERT biology.
1 is wrong because the 5' end of hnRNA receives a 7-mmG cap (7-methylguanosine cap), not at the 3' end. 3 is wrong because the template strand, not the coding strand, is used to synthesize mRNA; the mRNA sequence is similar to the coding strand (with U replacing T). 4 is wrong because split genes (introns) are a feature of eukaryotes, not prokaryotes.
🧠 Did You Know?
Rho-dependent termination requires the Rho protein to catch up with the RNA polymerase and unwind the RNA-DNA hybrid.
💡 NCERT Memory Line:
Rho factor-dependent termination occurs in some bacteria; transcription in prokaryotes uses a simpler termination mechanism than in eukaryotes.
Statement I: The condon 'AUG' codes for methionine and phenylalanine. Statement II: 'AAA' and 'AAG' both codons code for the amino acid lysine.
In the light of the above statements, choose the
correct answer from the options given below.
E.coli has only 4.6 × 106 base pairs and completes the process of replication within 18 minutes; then the average rate of polymerisation is approximately:
AI-generated explanation. Check against your textbook.
Explanation:
In NCERT biology, the term kinetin was coined by F. Skoog and Miller. They introduced and named this cytokinin when studying plant growth regulators from extracts (e.g., coconut milk) in the 1950s.
🧠 Did You Know?
Went contributed to early work on plant growth regulation and auxins; Darwin’s studies are foundational in tropisms; Kurosawa is associated with research on cytokinins, but the term “kinetin” was coined by Skoog and Miller.
💡 NCERT Memory Line:
Kinetin term coined by Skoog and Miller (not by Went, Darwin, or Kurosawa).