The sugar and phosphate portion of the nucleotides are found as segments of the rails on the DNA twisted ladder.
The evolutionary tree is not observed here but it is possible to answer this question by observing which nucleotide is found in the root of the node. It indicates the first substitution.
<h3>What is an evolutionary tree?</h3>
A phylogenetic evolutionary tree is a diagram used to show the evolution of a given taxonomic group (for example, a group of species).
It is possible to trace the evolution of a given taxon by tracing the nucleotide substitution observed from a common ancestor.
In an evolutionary tree, the root of the node is represented by the common ancestor and therefore the presence of a particular nucleotide (either T or C) in that position can be considered as the ancestral character.
Learn more about evolutionary trees here:
brainly.com/question/2189834
Answer:
macroevolution
Explanation:
Macroevolution is said to be the evolutionary changes that occur on a larger scale beyond a single species as a result of evolutionary forces such as mutation, gene flow, genetic drift. Macroevolution, unlike microevolution, usually results into the emergence of two new species with pronounced changes. The event as illustrated in the question is an example of macroevolution.
Chemoreceptors is the answer
