Answer:
An important source of genetic variation comes from mutations. A mutation is a change in the DNA sequence of a gene. Though some mutations are harmful, most are not. A mutation may change a trait in a way that may even be helpful, such as enabling an organism to better adapt to its environment.
The simplest mutation is a point mutation. This occurs when one nucleotide base is substituted for another in a DNA sequence. The change can cause the wrong amino acid to be produced. In some cases, the change has little effect. In other cases, the incorrect amino acid can affect the structure or function of the protein being encoded.
Here’s an example of how this works. This sentence composed of three-letter words is similar to a DNA sequence made up of three-base sequences called codon Now, what happens if one letter is changed?
The sentence now has a different meaning! Notice that the change affects just one word. If this was a DNA sequence, a change in one codon might not cause problems. But in some cases, it can have a severe effect. For example, here’s part of the DNA sequence for hemoglobin, a blood protein that carries oxygen to the tissues
Explanation:
