Answer:
The four nitrogen bases that are found in deoxyribonucleic acid (DNA) are adenine, cytosine, guanine, and thymine.
Thymine and cytosine comprise of one -carbon nitrogen ring and also called pyrimidines, while two carbon nitrogen ring is present in adenine and guanine and also called purines. Purines has larger in size because of extra carbon nitrogen ring.
The correct answer is (a.) a mutation of the hemoglobin allowing better oxygen-carrying capacity. The mutation of the hemoglobin that allows a better oxygen-carrying capacity would be the most beneficial to an elephant and its descendants.
Answer: <u>Sinks towards the outer core
</u>
Explanation: The material which is less dense, means it is lighter in weight. Such substances tend to move more towards the crust of the Earth, whereas the heavier substances like iron, is more towards the core or centre of the Earth. This is because heavier substances tend to sink deeper. That’s why the light elements are found in the crust section of the Earth.
