Answer:
hope this helps
Explanation:
About 95 percent of the time, Down syndrome is caused by trisomy 21 — the person has three copies of chromosome 21, instead of the usual two copies, in all cells. This is caused by abnormal cell division during the development of the sperm cell or the egg cell.
Answer:
D. Sunlight
Explanation:
Since photosynthesis provides the energy the plant needs for growth, lack of light will stunt the plant's growth.
Answer:
The correct option is H) these acids change the environment.
Explanation:
Soil can be described as the part of the environment where plants grow. In primary succession, life stars arising in an area which has no soil and only rocks, This is possible because lichens are the organisms which can grow on the rocks. Lichens secrete certain acids which break down these rocks and hence soil begins to form when these rocks break. This makes it possible for other plant species to grow on these lands.
Answer:
chemical property
Explanation:
Wood is a flammable substance. Depending how dry it is will determine its flammability or what temperature it will burst into flame. Burning wood undergoes chemical property changes: the brown hard wood becomes a black pile of ashes.