BYS 321: Chapter 9

Some virulence genes are carried on plasmids or by lysogenic bacteriophages.

true

Linking an ORF with a specific function is an example of gene

annotation

Chromosomal islands are similar to plasmids

because both elements contain nonessential genes

The field of study that can reveal how genes function, reveal how organisms interact with the environment, and show evolutionary relationships is ----

comparative genomics

Horizontal gene flow is accomplished in prokaryotes by ----

conjugation, transduction, and transformation

Gene duplication is essential to organisms because ----

duplicate genes are more able to evolve into new genes

Microorganisms that grow in extreme environments typically contain larger genomes when compared to microbes that grow in non-extreme environments.

false

Gene families are composed of homologous genes that have different evolutionary origins but the same function.

false Gene families are composed of homologous genes that are related in sequence and may be of the same origin.

The genome sequence of an organism can provide information about the organism's ----

genes, function, and evolutionary history

Which method is most commonly used in metabolomics?

mass spectrometry

Genes encoding compounds such as pyruvate, acetyl-CoA, fructose-6-phosphate, oxaloacetate, and other small organic compounds could be part of a(n)

metabolome

The entire complement of RNA produced under a given set of conditions is called a(n)

transcriptome

Most mobile DNA consists of

transposable elements

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

viral in origin

Chromosomal islands contain clusters of genes for

virulence, biodegradation of pollutants, and symbiotic relationships

Horizontally transferred genes typically encode essential metabolic functions such as DNA replication, transcription, and translation.

false Horizontally transferred genes typically encode for virulence factors or resistance.

Paralogs always have the same function.

false Paralogs similarity is the result of gene duplication at some time in the evolution of an organism.

Horizontal gene transfer refers to the transfer of genes from one organism to another, as occurs during conjugation between bacteria. How does this differ from vertical gene transfer?

In horizontal gene transfer, genes are transferred from one mature adult organism to another. In vertical gene transfer, genes are transferred from adults to offspring.

Researchers discover a new species of bacterium that has an unusual metabolism. However, it has biochemical and morphological similarities to other species. What is the most comprehensive and effective approach to determine how to classify these bacteria?

The bacteria should be classified by using genomic analyses to construct phylogenies.

An open reading frame (ORF) encodes for

a polypeptide

Arrange the following genetic components in the correct order.

genome, transcriptome, proteome, metabolome

Which "omic" is most directly involved in identifying molecules as possible drug targets that can be used to develop new medications?

genomics

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 ----

homologous/gene families

Horizontal gene transfer

is common and may sometime occur between unrelated organisms.

Transcriptome analysis is useful in relation to genome analysis because

it analyzes RNA, thus it reveals which genes are expressed under different conditions

Genomes of species in both Bacteria and Archaea show a strong correlation between genome size and

number of ORFs

You want to know whether the virulence genes present in Bordetella pertussis are evolutionarily related to genes in the less pathogenic species B. bronchiseptica or if the virulence genes were acquired via horizontal gene transfer. What characteristic(s) would you compare to answer this question?

percentage of GC content and codon usage

In Sanger sequencing and in many newer sequencing techniques, labeled precursors are used. What are these precursors?

primers or nucleotides that will be incorporated into the newly synthesized DNA

Which of the following is NOT included in the genome?

proteins

Gene function is annotated based on homology between the ORFs of a genome and proteins whose function has been proven experimentally. What -omic approach could help us determine the function and structure of proteins encoded by uncharacterized ORFs?

proteomics

Mobile DNA elements are more common in the genomes of

rapidly evolving species

The core genome of a prokaryotic species is the genomic content that is

shared between all other prokaryotes

Gene duplication is thought to have had a significant influence on the evolution of microbes because ----

the duplicated gene can be mutated, possibly leading to a useful new gene function or product, while the original copy can still perform its original (and possibly essential) genetic function

The very first DNA sequencing technology called the Sanger method relies on

the incorporation of dideoxynucleotides that terminate chain extension during DNA synthesis.

Microarrays can be used to

detect pathogens, analyze global gene expression, and detect unwanted food additives or substitutes

The total genetic complement of all cells within a microbial community is called a(n)

metagenome

If a researcher wanted to compare the enzymatic capacity to degrade compounds in a water column at various depths under a specific set of conditions, which would be the most useful approach?

metaproteomics

Chromosomal rearrangements due to insertion sequences have apparently contributed to the evolution of several human pathogens.

true

Codon usage varies from one organism to the next

true

Comparative genomics helps us to understand evolutionary relationships between organisms.

true

Genomic analysis led to the discovery that pathogenic organisms often lack genes for amino acid biosynthesis.

true

Knowledge of an organism's genome sequence yields important clues to how an organism functions and its evolutionary history.

true

Horizontal gene transfer has been thoroughly documented for genes involved in

virulence and metabolic functions