Chapter 9 Review

Which of these organisms is likely to have the largest genome? View Available Hint(s) A an autotrophic bacterium B a yeast cell C a chloroplast D an extremophile Archaean due to the demands of surviving in harsh environments

B a yeast cell

Gene duplication is essential to organisms because __________. View Available Hint(s) A duplicate genes slow down the possibility of evolution B duplicate genes are more able to evolve into new genes C duplicate genes prevent the evolution of new genes D duplicate genes will ensure the organism will always have a backup copy in case of mutation

B duplicate genes are more able to evolve into new genes

The largest cellular genomes belong to prokaryotes that are parasitic or pathogenic. True False

FALSE

In Sanger sequencing and in many newer sequencing techniques, labeled precursors are used. What are these precursors? a. primers or nucleotides that will be incorporated into the newly synthesized DNA b DNA polymerase c RNA d fluorescent dyes

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

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? a. metagenomics b metabolomics c transcriptomics d proteomics

d proteomics

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? View Available Hint(s) a. Because of their unusual metabolic pathways, the bacteria should be classified in a new group. b. The bacteria should be classified with other bacteria that have the most similar morphology. c. The bacteria should be classified with the other bacteria that use the most similar biochemical pathways. d. The bacteria should be classified by using genomic analyses to construct phylogenies.

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

An open reading frame (ORF) encodes for A a polypeptide. B a carbohydrate or a polypeptide. C a lipid. D a carbohydrate.

A a polypeptide.

Linking an ORF with a specific function is an example of gene A annotation. B expression. C codon bias. D assembly.

A annotation.

Horizontal gene transfer has been thoroughly documented for genes involved in... A translation. B virulence and metabolic functions. C only very few processes. D DNA replication and repair.

B virulence and metabolic functions.

Within Archaea and Bacteria, one megabase pair (Mbp) of DNA encodes about ________ open reading frames.

1000

Functional analysis of the genome of a prokaryote shows that 20% of the genome is for metabolism, 1 % for biosynthesis of amino acids, 8% for peptide ABC transporters, and 2% for replication. What can you determine about the environment in which this organism lives? View Available Hint(s) A The organism lives in an environment rich in organic material, particularly amino acids and proteins. B The organism lives in an environment rich in lipids. C The organism lives in an environment rich in hydrocarbons. D The organism lives in an environment rich in sugars.

A The organism lives in an environment rich in organic material, particularly amino acids and proteins.

The genome sequence of an organism can provide information about the organism's __________. A genes, function, and evolutionary history B function, evolutionary history, and morphology C genes, size, and function D function, size, and evolutionary history

A genes, function, and evolutionary history

Arrange the following genetic components in the correct order. View Available Hint(s) A genome, transcriptome, metabolome, proteome B genome, proteome, transcriptome, metabolome C genome, transcriptome, proteome, metabolome D genome, metabolome, transcriptome, proteome

C genome, transcriptome, proteome, metabolome

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? View Available Hint(s) A metabolomics B genomics C metaproteomics D metagenomics

C metaproteomics

The advantage(s) of second-generation DNA sequencing compared to the Sanger method are the result of A increased length of DNA sequences obtained. B increased computing power. C miniaturization of reaction size and increased computer power. D miniaturization of reaction size.

C miniaturization of reaction size and increased computer power.

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? A ribosomal binding site and intron sequence B genome size and number of introns C percentage of GC content and codon usage D number of genes in the pan genome

C percentage of GC content and codon usage

Which of the following is NOT included in the genome? A coding regions of DNA B genes that encode RNAs C proteins D noncoding regions of DNA

C proteins

The most abundant genes in prokaryotic genomes are A those involved in DNA replication. B those involved in translation. C those involved in metabolism. D those involved in transport.

C those involved in metabolism.

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 eukaryotic in origin. C viral in origin. D from extinct microorganisms.

C viral in origin.

Based on the evolutionary tree shown below, RubisCO Form II and RLP beta are orthologs. RLP alpha | RLP beta Ancestral gene | | RLP ancestor | | | | | Duplicate gene | RubisCO Form II | | ____RubisCO ancestor RubisCO Form I | | RubisCO Duplicate | RubisCO Form III

FALSE

A computer program recognizes an ORF by looking for ribosomal binding sites, start codons, and stop codons with an appropriate number of nucleotides between each element. What is a drawback of this approach? A We lack the computing power to complete the analyses in a timely manner, thus many genomes are only partially annotated. B Too many ORFS are identified, most of which are stretches on non-coding junk DNA. C Legitimate genes and non-coding RNA may be missed. D Codon bias causes incorrect annotations.

C Legitimate genes and non-coding RNA may be missed.

In DNA replication in vivo, RNA primers are used. However, researchers used DNA primers instead in the lab because DNA primers are more stable. Why might this be the case? A DNA has a more stable structure because the deoxyribose in DNA is a larger molecule than the ribose in RNA. B RNA is usually single-stranded, and the double-stranded nature of DNA makes it more stable. C RNA molecules are shorter than DNA molecules, making them more stable. D RNA has a relatively short half-life compared with DNA and does not need to be as stable to perform its functions in the cell.

D RNA has a relatively short half-life compared with DNA and does not need to be as stable to perform its functions in the cell.

Sequencing an organism's genome often leads to identification of hypothetical proteins, which are characterized as __________. A proteins that likely exist with known functions B proteins that are overexpressed C proteins that are expressed D proteins that likely exist though their function is unknown

D proteins that likely exist though their function is unknown

In general, prokaryotic genome size is linked to its metabolism and interaction with the environment. Which type of prokaryote typically has the smallest genome? A free-living heterotroph B endosymbiont C parasite D autotroph

endosymbiont