The Most Recent Identified Ancestor of Eukaryotes Is a Group

question 75

Multiple Choice

The most recent identified ancestor of eukaryotes is a group of Archaea called the lokiarchaeotes.The evidence of this phylogenetic relationship is based on the presence of certain genes in the lokiarchaeote genome.These genes

• A) confer a fitness advantage to archaea and are likely a result of horizontal gene transfer.
• B) are unique to prokaryotic archaea.
• C) are conserved in the two major divisions of life.
• D) are involved in fundamental biological processes that take place in eukaryotes.
• E) are more closely related to genes found in bacteria than to those found in eukaryotes.

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Definitions:

Spinous Process

A bony projection off the posterior (back) part of each vertebra, serving as a point for muscle and ligament attachment.

Costal Facet

A small, flat surface on a vertebra that articulates with the rib, contributing to the thoracic cage's stability.

Lamina

A thin layer, plate, or scale of organic material, such as the lamina of a vertebrate's bone or the lamina propria in mucous membranes.

Xiphoid Process

A small cartilaginous extension of the lower part of the sternum which is usually ossified in the adult human.