Answer:E. Adenine and Guanine
Explanation:
They are double <u>double carbon- nitrogen rings with four nitrogen atoms</u> bases found in DNA and RNA. Purines always pair with pyrimidines(cytosine and thymine) to form a double helix structure.This precise paring ensured that the DNA has a complementary structure.
This paring of purines with pyrimidines is by hydrogen bonds. This is to ensure easily unwinding during replication, that is formation of new DNA molecules.
purines bases are also used for cell protein synthesis fro cell division.
<span>In contrast to a cerebral concussion, a cerebral contusion </span>involves physical injury to the brain tissue. Cerebral Concussion is a <span>Traumatic brain injury.</span>
Because the sun heats up the sand causing the atoms to move much faster than at night
