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wwwaazup
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In DNA, the base pairs are on the inside of the heli. Eplain why purine-purine and pyrimidine-pyrimidine base pairs do not occur, only purine-pyrimidine base pairs?
Purine bases (adenine and guanine) have a double-ring structure, while pyrimidine bases (thymine and cytosine) have a single-ring structure. This difference in size and structure allows for proper hydrogen bonding between the bases, leading to stable base pairing.
Purine-purine and pyrimidine-pyrimidine base pairs are not as energetically stable as purine-pyrimidine base pairs. Therefore, having purine and pyrimidine bases pair with each other ensures the stability of the DNA molecule.
No, purine-purine and pyrimidine-pyrimidine base pairs are not found in DNA as they are not energetically favorable. The correct base pairing between purines and pyrimidines is essential for maintaining the stability and function of DNA.
Purine-purine and pyrimidine-pyrimidine base pairs have a different shape and size compared to purine-pyrimidine base pairs. This difference in structure can cause distortions in the DNA molecule, leading to instability and potential mutations.
There are some exceptions to this rule, such as in RNA where adenine can pair with uracil (a pyrimidine). Additionally, certain DNA repair enzymes can temporarily form purine-purine or pyrimidine-pyrimidine base pairs during the repair process. However, these exceptions are temporary and do not affect the overall base pairing rules in DNA.