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.
<span>Sheet fractures are accurate fractures defining slabs of rock that range from 0.5 to 10 meters thick. They normally form in sets parallel to the Earth's surface but may form in convex-upward or concave-upward sets. The most popular hypothesis of the formation of sheet fractures is that they are the result of expansion and tangential fracturing consequent on erosion offloading or pressure release.</span>
Decrease as the more frogs there are the more flies will be eaten so that means the flies will decrease.Also if the flie population gets low enough the frog population would shrink too to balance it.
Answer:
Explanation:
Hippocampus is important for forming long term memories, while the Prefrontal cortex is responsible for memories retrieval.