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MODEL PAPER 8 — BIOLOGY STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceBIOLOGYMODEL PAPER 81 Mark
MCQ
Assertion (A): Potassium is only essential for animals.
Reason (R): Along with sodium is essential for the conduction of impulses in nerve cells.
  • A
    Both A and R are true and R is the correct explanation of A.
  • B
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

(d) A is false but R is true.
Explanation: Potassium fluxes govern the movements of stomata and the movement of variations in several plants including Mimosa pudica (Seismonasty) and Oxalis (nyctinasty). Its deficiency in plants affects processes such as respiration, photosynthesis, chlorophyll development, and the water content of leaves.

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