Alternating sugar and phosphate molecules also 4 types of nitrogen bases
Answer:
Cytosine
Explanation:
Purine, Adenine, and Guanine are all purines
Answer:
Option B, Mammals and reptiles in the post-dinosaur age.
Explanation:
Adaptive radiation is mechanism through which species evolve very fast from common single ancestors. In simple words two different species are said to have evolved through adaptive radiation when they have descended from a single lineage. This is not the case with mammals and reptiles.
Generally in adaptive radiation, a species evolve when it faces new environmental challenges due to change of habitat or area. For example mammals have evolved from dinosaurs.
Hence, option B is correct
The gaps (approximately 1 micrometer wide) formed between myelin sheath cells long the axons are called Nodes of Ranvier. Since fat serves as a good insulator, the myelin sheaths speed the rate of transmission of an electrical impulse along the axon.
