The factors that affect personal health that are the most easily controlled are c) lifestyle.
You can easily change the way you are living, whereas these other things cannot be.
The correct answer is:
The principal cause of aneuploidy is chromosome nondisjunction during mitosis or meiosis. Polyploidy in nature can result either from the duplication of euploid chromosome sets from a single species or from the combining of chromosome sets from different species.
Aneuploidy is a phenomenon when there is the presence of an abnormal number of chromosomes in a cell (an extra or missing chromosome). Usually it appears as a result of improper cell division (chromosomes don’t separate) and it can cause many genetic disorders.
Polyploidy refers to a state when there are more than two sets of chromosomes (one from mother one from father). Triploid (three sets of chromosomes) and tetraploid (four sets of chromosomes) chromosomes are examples of polyploidy. This phenomenon is most common in plants.
Explanation:
If water did not expand when freezing, then it would be denser than liquid water when it froze; therefore it would sink and fill lakes or the ocean from bottom to top. Once the oceans filled with ice, life there would not be possible.
If the immune system fails to produce proteins (Antibodies) it can cause a disease. This is because our immune systems are very needed so if our immune system decides to fail to produce its proteins, our body will become overwhelmed and could possibly cause us to die! :(