Question

Which of the following are incorrect as a criterion for the essentiality of an element .
i. If the concerned element is deficient another element can fulfil the need of it
ii. The plants would complete their life cycle irrespective of the absence of deficiency of the elements.
iii. The elements have indirect involvement in the metabolism of plants .
iv.The elements must be absolutely necessary for supporting normal growth and reproduction .

Answer 1

Answer:

Correct option is

D

Indirectly involved in plant metabolism.

Arnon and Stout (1939) proposed criteria for knowing the essentiality of an element. There are:

(i) It is indispensable for the growth of plants.

(ii) The element is directly involved in the metabolism of plants.

(iii) A plant is unable to complete its vegetative or reproductive phase in the absence of the element.

(iv) The element cannot be replaced by any other element.

(v) The absence or deficiency of the element produces disorders. These disorders are a direct result of the lack or deficiency of the element.

So, the correct answer is 'Indirectly involved in plant metabolism'.