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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: Ribosomes attached to endoplasmic reticulum release proteins into lumen of $\text{ER}.$
Reason: Such proteins are used for formation of hydrolytic enzymes or are modified.
  • 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.
Polyribosomes attached to membranes of endoplasmic reticulum produce proteins which either pass into their lumen or become integrated into the membranes. The proteins released into the lumen generally reach Golgi apparatus for modifications like formation of hydrolytic enzymes and glycosylation $($addition of sugar residues$).$ The modified proteins are packed in vesicles for export or formation of lysosomes, cell wall enzymes, plasma membrane, etc.

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