NEET Zoology - MCQ Practice Questions

Disruptive selection eliminates intermediate phenotypes and favors both extreme phenotypes, increasing genetic variation.

Common descent refers to the principle that all organisms share evolutionary ancestry, a fundamental concept in evolutionary biology.

Homologous structures (similar structures with different functions) indicate common ancestry and provide strong anatomical evidence for evolution.

Heterozygous female (X^W X^w) × normal male (X^W Y) produces X^W X^W and X^W X^w females, both with normal eyes. White eyes appear only in males (X^w Y) at 50%.

Allopatric speciation begins with geographic isolation, followed by independent genetic drift and mutations in isolated populations, leading to reproductive isolation and eventually new species formation.

Using Hardy-Weinberg equation: frequency of Aa = 2pq = 2(0.7)(0.3) = 0.42. This remains constant across generations in equilibrium.

These structures share similar bone arrangements despite different functions, indicating descent from a common ancestor with modification—evidence for divergent evolution.