Adenine forms two hydrogen bonds with thymine in DNA while three hydrogen bonds are formed between guanine and cytosine.
Thymine and cytosine are pyrimidines because they have a single ring structure. Adenine and guanine are purines because they have a double ring structure.
This representates the temperature of F degrees Fahrenheit converted to degrees Celsius. Remember that in order to change temperature we need to use the following formula: <span>from Fahrenheit to Celsius: first subtract 32, then multiply by 100/180</span>
Answer: "natural selection" .
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Hydrogen bonds connecting base pairs must be broken.
Photosynthesis occurs in plant cells, but does not occur in animal cells.