they are essential to its health. As dead wood is decomposed it aids new plant growth by returning important nutrients to the ecosystem.
Answer:
A
Explanation:It boils down to a and b. A single molecule of DNA is wrong. So it's a,
Answer:
False
Explanation:
In the troposphere, near the Earth's surface, human activities lead to ozone concentrations several times higher than the natural background level. Too much of this ground-level ozone is 'bad' as it is harmful to breathe and also damages vegetation.
The stratosphere or “good” ozone layer extends upward from about 6 to 30 miles and protects life on Earth from the sun's harmful ultraviolet (UV) rays.
Often times, non-human life in an urban ecosystem is more disturbed in a way that changes happen rapidly, such as the soil and plant cover and temperature and water availability