Explanation:
In the majority of cases, the extra copy of chromosome 21 comes from the mother in the egg.
In a small percentage (less than 5%) of cases, the extra copy of chromosome 21 comes from the father through the sperm.
In the remaining cases, the error occurs after fertilization, as the embryo grows.
You are correct the answer is c
Answer:
No,
Although the atmosphere is mostly made up of nitrogen, it is in the form of gas known as dinitogen N2. Plant cannot use this form.
Explanation: