Marriages or any form of sexual relations between blood relatives is incest and is completely prohibited in the United States and most other countries of the world.
There are two reasons for this:
1. Religious: Most major world religions prohibit marriages between blood relatives. In countries where church and other religious institutions had a strong following, incest remains a crime.
2. Biological: Medical Science has proven that off-springs of close relatives e.g. brother-sister, first cousins and even second cousins have a high chance of genetic mutation which can lead to various health issues. This is the main reason why modern societies prohibit incest
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Answer:
initially by meiosis, then by mitosis( last choice)
A cell that just fertilized has to divide 6 times to form a 64 cell blastomere.
<u>Explanation:</u>
Human reproduction begins with the fusion of male gamete sperm and female gamete ovum. The fusion of sperm and ovum forms the zygote that is diploid. The zygote then undergoes mitotic division to develop into embryo.
The zygote first divides into two and the two individual cells divide again to form four individual cells and so on. Thus the number of cells after each division can be represented by the equation 
where n is the number of divisions. in the question it is given that the blastomere has 64 cells.
n=6
This means that the fertilized cell has to divide 6 times to develop into 64-celled blastomere.
