Biological soil crusts<span> are communities of living organisms on the </span>soil<span> surface in arid and semi-arid ecosystems. They are found throughout the world with varying species composition and cover depending on topography, </span>soil<span> characteristics, climate, plant community, microhabitats, and disturbance regimes.</span>
In any imbalance of nerve endings are very important people can die <span>for it is very sensitive nerve endings</span>
I believe the answer is Volcanic glass
I would say "gene", as it is the basic unit of heredity.<span />
Plants get their energy from the Sun. animals would then eat the plants and get energy from the plants.