Assertion (A): Potassium is only essential for animals. Reason (R… - Vidyadip

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.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Assertion & Reason" from MODEL PAPER 8→MODEL PAPER 8 — all question types→BIOLOGY STD 11 Science question papers→Rajasthan Board STD 11 Science question papers→Rajasthan Board question paper generator→

Similar questions

Assertion (A): The amount of $CO2$ that can diffuse through the diffusion membrane per unit difference in partial pressure is much higher compared to that of $O _2$.
Reason (R): The solubility of $CO _2$ is 20-25 times higher than that of $O _2$.

Assertion (A): Food vacuoles of Paramecium are noncontractile vacuoles.
Reason (R): They are meant for extracellular digestion.

Assertion (A): Excessive inflation of the lungs is prevented by the Hering-Breuer reflex.
Reason (R): On overstretching of the lungs, the stretch receptors send impulses along the vagus nerve to stimulate the expiratory centre.

Assertion : Gram-negative bacteria do not retain the stain when washed with alcohol.
Reason : The outer face of the outer membrane of gram-negative bacteria contains lipopolysaccharides, a part of which is integrated into the membrane lipids.

Assertion (A): Inspiration is initiated by the contraction of the diaphragm which increases the volume of the thoracic chamber in the antero-posterior axis.
Reason (R): The contraction of external intercostal muscles lifts up the ribs and the sternum causing an incn in the volume of the thoracic chamber in the dorso-ventral axis.

Assertion (A): Amylase enzyme stops its activity in stomach.
Reason (R): In stomach, pH is acidic due to presence of HCl.

Assertion (A): Voice of women and children is high pitched whereas that of men is low pitched.
Reason (R): Vocal cords of men are longer than of women and children.

Assertion: Living organisms have more nitrogen and oxygen per unit mass than inanimate objects (e.g., earth crust).
Reason: Living organisms have more Ca, Mg, Na in them than inanimate object.

Assertion (A): In certain industries, especially those involving grinding or stone-breaking, so much dust is produced, a long exposure can give rise to occupational respiratory disorders.
Reason (R): It produces inflammation leading to fibrosis and thus causing serious lung damage.

Assertion (A): Elemental analysis gives the elemental composition of living tissues in the form of hydrogen
Reason (R): Wet weight is the weight of living tissue and the remains of living tissue after drying gives dry weight.