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Origin and Evolution of Life — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYOrigin and Evolution of Life3 Marks
Question
Explain the following terms: (a) Gene mutation (b) Genetic recombination (c) Gene flow
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Answer

(A) Gene mutation : Some time mismatch combination of nitrogenous bases occurs in the DNA. If this change results in the alteration of the function of the gene it is called gene mutation.

(B) Genetic recombination : The new genetic combinations from the pre-existing parental genes are called genetic recombinations.

(C) Gene flow : Gene flow is the transfer of alleles or genes from one population to another. This causes change in the composition of the gene pool of the receiving population. This is necessary for the process of evolution. When the gene flow stops, there will be no evolution.

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