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MODEL PAPER 7 — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMODEL PAPER 73 Marks
Question
While creation and presence of variation are directionless, natural selection is directional as it is in the context of adaptation. Comment.
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Answer

Variations keep on occurring in each subsequent generation. But most of them may not be retained by the organism because nature may not support such variations. When a particular variation passes the test of natural selection, then only it is inherited in a species in the long run. Hence, it can be said that creation and presence of variation is directionless but natural selection and adaptation are directional.

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