The first three are the same as those found in DNA, but in RNA thymine is replaced by uracil as the base complementary to adenine. This base is also a pyrimidine and is very similar to thymine. Uracil is energetically less expensive to produce than thymine, which may account for its use in RNA.
When focusing on a slide, ALWAYS start with either the 4X or 10X objective. Once you have the object in focus, then switch to the next higher power objective.
<u>Density</u> – The amount of matter in a given space. In scientific terms, density is the amount of mass in a unit of volume.
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The amount of matter in a given amount of space is known as the <u>Density.</u>
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For an animal to be extinct none more of that specific species must exist on Earth. This makes it impossible for that species to come back to life.