Describe how mutations arise and their significance in evolution.

Answer:

-Mutations arise due to change in number of chromosomes; or portion of chromosome affecting one or more genes; they may be chromosomal aberration or deletion/duplication/ inversion/ translocation/ crossover; by mutagenic agents; e.g. radiation (X-ray, Ultra violet rays, gamma rays) and chemical substances e.g. mustard seed;
-Mutations bring about variations; which can be inherited; some of these variations are advantageous to the organism; others are disadvantageous to the organism; to compete better in the struggle for survival; this results into a more adapted organism to its environment; or new varieties/ species; those with disadvantageous characters will be discriminated against; therefore eliminated from the population/ perish;

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