The differences that occur at the molecular level or in the genes, will result in changes in the proteins which the genes code for bringing about variation in traits.
What is variation?
Variation refers to the changes that occur between individuals of the same species due to environmental or genetic factors.
The basis for variation is differences that occur at the molecular level.
The genes are regions of the DNA which code for a particular trait.
The DNA is composed of chains of polynucleotide molecules.
When differences occur at the molecular level or in the genes, the proteins which the genes code for will have differences in structure.
Thus, the individuals will show variation as in the case of the two sisters who show variation in height and hair structure.
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