Hydrogen bonds<span> hold the paired nitrogenous bases together. Because </span>hydrogen bonds<span> are weak </span>bonds<span>, the two strands of </span>DNA<span> are easily separated a characteristic that is important to </span>DNA's<span> function.</span>Hydrogen bonds<span> form between adenine and thymine and between cytosine and guanine.</span>
When a fuel burns, it combines with oxygen int the air and changes into the substances water and carbon dioxide. That's how Flammability is a chemical property.
Answer:
Second Earth's Atmosphere
The second atmosphere, which was the first to remain with the earth, was created by volcanic outgassing and comet ice. There was a lot of water vapor, carbon dioxide, phosphorus, and methane in this atmosphere, but absolutely no oxygen.
Explanation:
Plant cells, along with every other cell, needs oxygen,carbon, and nitrogen. These are basically the elements every living cell needs to survive.
Plant cells also need sunlight for photosynthesis and produce sugar to convert that into food. <span />
