Question

Statement I:Disruptive selection operates when homogeneous environment changes into a heterogeneous type. Statement II: Change the frequency of a gene that occurs by chance and not by selection in small populations is called directional selection

• A. Both statements I and II are true
• B. Both statements I and II are false
• C. Statement I is true. But II is false
• D. Statement I is false. But II is true

Hint:

Disruptive selection leads to the development of two distinct phenotypes from a single population, while directional selection favors one extreme phenotype.

Answer 1

The Correct Option is C

Step 1: Disruptive selection occurs when a homogeneous environment changes to a heterogeneous environment, leading to the formation of different types. This is the first statement and it is true. 

Step 2: The second statement is incorrect because the frequency change of a gene due to chance and not selection in small populations is called genetic drift, not directional selection. Directional selection occurs when one extreme phenotype is selected, not when chance alone drives genetic changes. Thus, statement I is true, but statement II is false.