The of a phylogenetic tree represents the common ancestor, the represent events where lineages diverged, and the axis represents time. assume that the tree is oriented as described in the textbook.

a. root

b. nodes

c. horizontal

Explanation:

Systematics, as we have already indicated, is the part of science that tries to find out the degree of diversity and differentiation of organisms, as well as the kinships and affinities between them. This is based on the results of other disciplines such as Cytology, Anatomy, Palinology, Embryology, Phytochemistry, Genetics, Geobotany, etc. On the other hand, taxonomyi the part of the Systematics that deals with the theoretical study of classification (ordering of beings in class hierarchies), including in it its bases, principles, methods and laws; vegetable taxonomy, therefore, deals with the description, nomenclature and arrangement of living plants

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.