MHT CET Medical202621 April 2026Evening ShiftBiologyMineral NutritionActual
Mn toxicity develops deficiency symptoms of Ca, Mg and Fe because
Options
- AMn competes with Fe, Mg for translocation.
- BMn stimulates Ca translocation to shoot apex.
- CIt causes excess absorption of Ca, Fe and Mg.
- DMn competes with Fe, Mg for uptake and inhibits translocation of calcium.
Correct answer
D. Mn competes with Fe, Mg for uptake and inhibits translocation of calcium.
Step-by-step solution
Manganese toxicity leads to the appearance of brown spots surrounded by chlorotic veins. Manganese competes with iron and magnesium for uptake from the soil and with magnesium for binding with enzymes. Manganese also inhibits calcium translocation to the shoot apex. Therefore, excess of manganese induces deficiencies of iron, magnesium, and calcium. Answer: Mn competes with Fe, Mg for uptake and inhibits translocation of calcium.