Question

It is possible to determine whether an element is essential by observing growth of plants.

• A. On soil in which the particular element is removed.
• B. On soil in which only the particular element is present
• C. On an inert medium to which solution of only the particular element is added
• D. On an inert medium to which a nutrient solution excluding that particular element, is added.

Answer 1

The correct option is D On an inert medium to which a nutrient solution excluding that particular element, is added.

Julius von Sachs, a German botanist, was the first to grow plants to maturity in a nutrient solution in the complete absence of soil. This technique of growing plants in a soil-free, nutrient solution is ‘Hydroponics’. The essential minerals were identified by adding or omitting an element in the nutrient solution or using varying concentrations. As we cannot grow a plant using only one mineral, for knowing what role does a particular mineral plays we can grow a plant in medium to which a nutrient solution excluding that particular element, is added.

So, the correct option is 'On an inert medium to which a nutrient solution excluding that particular element is added'.