Earth and its atmosphere are continuously altered. Plate tectonics shift the continents, raise mountains and move the ocean floor while processes not fully understood alter the climate. Such constant change has characterized Earth since its beginning some 4 billion years ago.
The answer is D. It <span>keeps outside substances away from the receptor cells</span>
These scientists all carried out experiments in accordance with the basic biological principle that life comes from pre-existing life. They investigated the theory of spontaneous generation and proved that life comes from life.
This also demonstrates that science is a way of knowing because they used what they saw in these experiments in other situations as well. They became able to do this only because they knew about this information and they got to know this information through science.
T<span>he </span>formula for cellular respiration<span> is glucose plus oxygen yields carbon dioxide, water and ATP, written as C6H12O6 + 6O2 --> 6H2O + 6CO2 + ATP.</span>
