GENETIC VARIATION: what are genetic variations?

This refers to differences among individuals of the same species which can be passed on from parents to their offspring; such variation are due to the changes in gene or due to changes in chromosome that carries gene. Genetic differences reflect the genotype of an organism i.e it’s the genetic makeup. The diploid organisms have two set of chromosome and two forms (alleles) of each particular gene. The alleles may be the same (in homozygous organism) for that gene or one is dominant and the other recessive in heterozygous organism. If an organism is haploid all its alleles will be reflected in its observable character, features or traits which are transmitted from parent to offspring. It can be influenced by any of the following
crossing over in meiosis, when genes break and re-attach causing genetic exchange of gene or chromosome
-fertilization in organism which is random
-recombination at random
-blending of features as a result of incomplete dominance
-effect of multiple alleles as in blood group inheritance

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