A surprising finding of environmental metagenomic studies is that a majority of genes in the ...

A surprising finding of environmental metagenomic studies is that a majority of genes in the environment are
 
  A) from microbes grown in the lab.
  B) viral in origin.
  C) eukaryotic in origin.
  D) from extinct microorganisms.

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Horizontal gene transfer
 
  A) is rare and only occurs between closely related strains.
  B) is common and may sometime occur between unrelated organisms.
  C) does not provide an advantage to organisms.
  D) only occurs in prokaryotes.

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Genes from different sources that are related in sequence due to shared evolutionary ancestry are called ________ genes, and groups of such genes are known as ________.
 
  A) homologous / gene families
  B) paralogous / functional genes
  C) orthologous / gene families
  D) homologous / functional genes

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Typically ________ of ORFs in a genome cannot clearly be assigned a function. These ORFs are usually assigned and predicted to encode hypothetical proteins.
 
  A) < 1
  B) 5
  C) 30
  D) 90

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RNA-Seq analysis is a method aimed at defining a(n)
 
  A) metabolome.
  B) transcriptome.
  C) interactome.
  D) metagenome.