Answer:
The Miller-Urey experiment was conducted to simulate the conditions on Earth when life arose, and see if a chemical evolution could occur. This experiment was performed without oxygen, because they knew that if oxygen was added, the amino acids would oxidize. In particular, the experiment intended to simulate a volcanic eruption was analyzed.
Thus, particles of water, methane, ammonia and hydrogen were exposed to high temperatures and electric discharges that simulated these eruptions, during a determined period. Later, it was observed that organic compounds had emerged from this exposure, which allowed us to infer one of the hypotheses regarding the origin of life on Earth.
The pH scale measures how basic or acidic a substance is, and it ranges from 0 to 14. On the pH scale, a pH of 7 is neutral, less than 7 is acidic and higher than 7 is basic.
Answer:
Gas exchange during respiration occurs primarily through diffusion. Gas molecules move from a region of high concentration to a region of low concentration. Blood that is low in oxygen concentration and high in carbon dioxide concentration undergoes gas exchange with air in the lungs.
Explanation:
The answer would be : <span>B. the Casparian strip is waterproof.
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Photon</span>