Assertion Polymorphism is the existence of two or more forms of the same species within the same population
Balanced polymorphism occurs when different forms coexist in the same population in a stable environment

Options

A. Both Assertion and Reason are true, but Reason is the correct explanation of Assertion
B. Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion
C. Assertion is true, but Reason is false
D. Assertion is false, but reason is true

Answer

B

Explanation

Polymorphism is the existence of two or more forms of same species within same population and can apply to biochemical, morphological and behavioural characteristics
Balanced polymorphism This occurs when different forms coexist in the same population in a stable environment Example exisrence of two sexes in animals and plants Existence of A, B, AB and O blood groups . Red-green `+-` colour blindness .
Existence of workers, drones, and queens in social insects
Transient polymorphism This arises, when different forms or morphs exist in a population undergoing a strong selection pressure
The frequency of the phenotypic appearance of each form is determined by the intensity of the selection pressure
Transient polymorphism usually applies in those situations where one form is gradually being replaced by the another- example,Melanic and Non-melanic forms of the peppered moth