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Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYMolecular Basis of Inheritance1 Mark
MCQ
For question, two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: The subunits of ribosomes come together only at the time of protein formation.
Reason: $Mg^{2+}$ causes their association or dissociation.
  • A
    Both assertion and reason are true, and reason is the correct explanation of assertion.
  • ✓
    Both assertion and reason are true, but reason is not the correct explanation of assertion.
  • C
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false
✓

Answer

Correct option: B.
Both assertion and reason are true, but reason is not the correct explanation of assertion.
During protein synthesis, two subunits of ribosomes associate.
$Mg^{2+}$ is essential for it. Soon after the completion of protein synthesis, the subunits separate. The phenomenon is called dissociation.

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