Adenine which is a purine base, always pairs with the pyrimidine Thymine in DNA and Uracil(also a pyrimidine) in RNA. The bond which is present between the two bases is a double hydrogen bond.
Guanine which is also a purine base, always pairs with the pyrimidine Cytosine, in the case of both, DNA and RNA. The bond which is present between the two bases is a triple hydrogen bond and hence, is stronger than the A-G double bond.
Explanation:
This electron exchange results in an electrostatic attraction between the two atoms called an ionic bond. An atom that loses one or more valence electrons to become a positively charged ion is known as a cation, while an atom that gains electrons and becomes negatively charged is known as an anion.
Sediment; There is a source of heat that was not included in the question to create all the other choices.
The central element for all living things is carbon, which is why you might often hear the phrase "carbon-based" lifeforms. Another term is often "organic matter"
