The inorganic element that helps in converting food into usable energy is:

Which element shows the given characteristics?
$(i)$ It maintains an anion-cation balance in cells.
$(ii)$ It is also involved in protein synthesis.
$(iii)$ It is required for the opening and closing of stomata.
$(iv)$ It is required for the maintenance of the turgidity of cells.

Phosphorus works as a carrier of which of the following elements?

Which is essential for the growth of root tip?

Which of the following is not a macro-nutrient?

Which of the following groups of elements are mobile?