The introductory passage discusses how researchers learned more about the relati

Question

The introductory passage discusses how researchers learned more about the relationships between Bacteria, Archaea, and Eukarya from studying the new Archaeal phylum Lokiarchaeota.

Which of the following is true about the evolutionary origin of all three of these domains?

Despite all of the research into the origins of the domains, there is still much to be learned. This is illustrated by the way that studying Lokiarchaeota led to new insights.

The introductory passage describes the identification of eukaryotic signature genes in Lokiarchaeota, explaining that these suggest that bacteria were acquired by archaeal cells to give rise to the Eukarya. Prior to this event, a series of events needed to take place in order for life to arise on Earth. Put the events below into the correct order to summarize the hypothesized path from prebiotic chemistry to evolutionary diversification, beginning with the earliest event.

Place the items below in the correct order. Items may overlap if events occur simultaneously.

Bacteria and Archaea
diverged.

Self-replicating
and catalytic
RNA developed
(the "RNA
world").

Archaea and Eukarya
diverged.

Biological building
blocks (amino
acids, nucleosides,
and sugars)
appeared.

DNA genomes
developed,
along with the
processes of
DNA
replication and
transcription.

Protein synthesis
and protein
enzymes
appeared.

Lipid bilayers
surrounded
the earliest cells
and allowed the
formation
of cellular
compartments.

Submit

In early cells, horizontal gene transfer was extremely important for the spread of beneficial genes. It is hypothesized that horizontal gene transfer occurred at high rates in these cells. Some genes transferred in this way allow microbes to act as pathogens, whereas others (housekeeping genes) are required for cell maintenance and homeostasis.

Part C - Pathogenic versus Housekeeping Genes

In studying Lokiarchaeota, researchers identified eukaryotic signature genes and used this information to better understand the relationship between archaeans and eukaryotes. Many other types of genetic analysis can be used that focus on certain types of genes. One example of this is multilocus sequence typing (MLST), which focuses on examining genes called housekeeping genes. Microbes encode both housekeeping and pathogenic genes in their genome. Drag the examples of genes to the correct bins to indicate whether they are housekeeping genes, pathogenic genes, or eukaryotic signature genes.

categorize phrases as either housekeeping genes, pathogenic genes, or eukaryotic signature genes:

membrane lipid genes

endotoxin genes

membrane remodeling genes

ribosomal genes

exotoxin genes

cytoskeletal genes

peptidoglycan synthesis genes

Housekeeping genes

Pathogenic genes

Eukaryotic signature genes

It is not yet clear whether the domains shared a common ancestor. Each domain of organisms evolved separately and independently. All of these domains evolved from an archaeal organism called Luca. All of these domains evolved from a shared ancestor known as LUCA.

Explanation / Answer

Part A- each organisms of domain evolved separately and independentmy

Part B- biological building blocks appeared

self replicating RAN (RAN world)

Bacteria and archea diverged

DNA genome developed along with the process of DNA replication and transcription.

Protein synthesis and protein enzyme appeared

Lipid bilateral surrounded the earliest cells and allowed the formation of cellular compartments

Archea and eucarya diverged.

PART C- Housekeeping genes : ribosomal genes and pepsitoglycan synthesis genes

Pathogenic genes : endotoxin genes and endotoxin genes

Eukaryotic signature genes : membrane lipid genes, membrane remodelling genes and cytoskeletal genes

Hope it helps !

Thank you

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