The answer is B Avoiding a friend with whom you've recently had an argument, and spending time with friend with whom your're still on friendly terms.
In the nervous system which works on various organs in the body that control blood pressure , heart rate , liver functions etc
Nondisjunction is defined as the failure of the chromosomes to seperate during cell division. An animal with a haploid number of 6 (diploid number of 12) undergoes meiosis, and at the meiosis II (cells are already haploid from the meiosis I), nondisjunction occurs. The mature ovum will contain 6+1 chromosomes (n+1) because there is an extra chromosome from the nondisjunction. The second polar body will contain 5 chromosomes (normal would be 6) because the second polar body did not receive that extra chromosome due to nondisjunction. In the event of fertilization of the abnormal ovum with a normal sperm, the zygote will be a diploid (12 chromosomes) normally but since the ovum as an extra chromosome from the nondisjunction then the zygote will have an extra chromosome (13 chromosomes). One pair of chromosomes has an extra single chromosome and this is called a trisomy.
