The Following Question Refers to This Phylogenetic Tree, Depicting the Origins

question 51

Multiple Choice

The following question refers to this phylogenetic tree, depicting the origins of life and the three domains. Connecting lines indicate instances of gene or genome transfer and time is indicated from left to right. A possible phylogenetic tree for the three domains of life.
If the early history of life on Earth is accurately depicted by the figure, then which statement is most in agreement with the hypothesis proposed by this tree?

• A) The last universal common ancestor of all extant species is one individual species.
• B) A significant amount of horizontal gene transfer occurred early in the evolution of life.
• C) Archaean genomes should not contain genes that originated in bacteria, and vice versa.
• D) Eukaryotes are more closely related to archaeans than to bacteria.

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Definitions:

Viscosity

Resistance to flow or alteration of shape by any substance as a result of molecular cohesion.

Interferon

A group of signaling proteins made and released by host cells in response to the presence of pathogens like viruses, bacteria, parasites, and tumor cells.

Virus Production

The process by which viruses replicate themselves within host cells, resulting in the production of new virus particles.

Infected Tissues

Body tissues that have been invaded by pathogenic microorganisms, leading to disease or inflammation.