Answer:
About 10% to 15% of adult colds are caused by viruses also responsible for other, more severe respiratory illnesses.
B
Explanation:
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.
Hi Ace22704,
Answer - natural observation
I think this experimental method is a better option because its in a natural environment where the kids dont know whats happening unlike the suveys where you ask them questions which is probably a bad idea because they might feel scared and just change their minds.