Chapter 21: Genomes, Proteomes, and Bioinformatics
How many genes are generally found for every million bases of prokaryotic DNA? 10F 100 1,000 10,000 100,000
1,000
You are part of a research team trying to sequence the genome of bacterial species X, which has a genome size of 2.2 Mb. You plan to use shotgun DNA sequencing and want to sequence at least 99% of the genome. How many Mb of DNA should you sequence? 10.13 4.61 0.01 9.02
10.13
Which of the following most adequately describes how the Alu element may have proliferated to constitute 10% of the human genome? Multiple retroelements code the same gene. Retroelements increase with every generation. A single retroelement can be copied into many RNA transcripts. Retroelements increase with each cell division. Retroelements show self-proliferation.
A single retroelement can be copied into many RNA transcripts.
Which of the following is a permanent post-translational covalent modification? attachment of a sugar disulfide bond formation proteolytic processing attachment of a lipid All of the choices are correct.
Attachment of a sugar
Researchers are interested in the genomes of prokaryotic species for all of the following reasons EXCEPT: Bacteria cause many diseases that affect people, plants, and animals. Bacteria reveal modes of infection. Bacteria are more highly advanced than humans. The origin of the first eukaryotic cell probably involved a union between an archaeal and a bacterial cell. All of the choices are reasons for studying genomes of prokaryotic species.
Bacteria are more highly advanced than humans.
What is true of the comparison between the myosin gene between a rat and a mouse? The nucleotide sequences are identical. The genes encode for different proteins. Each species has accumulated random mutations, but the sequences are similar. Both species are so far apart that there is no homology between the two sequences. The genes encoding myosin closely resemble those encoding actins.
Each species has accumulated random mutations, but the sequences are similar.
A researcher is interested in comparing the DNA sequence for the gene encoding myosin between a cheetah (mammal) and a red snapper (fish). Which database would be most helpful to her? GenBank Swiss Prot PIR (Protein Information Resource) GenPept PDB (Protein Data Bank)
GenBank
Some biologists argue that transposable elements provide benefits to a given species. Which of the following does not describe a potential benefit offered by transposable elements? Codes for a gene that increases survival. Increases genetic variation. Inserts into functionally important genes. Codes for a gene that confers antibiotic resistance.
Inserts into functionally important genes.
A researcher has mapped the entire genome of an insect. She notices that the genome contains around a thousand copies of a particular DNA sequence. What is the most likely function of this DNA sequence? The sequence most likely has no function. Its function is to code for rRNA. Its function is to provide antibiotic resistance. Its function is to copy and move within the genome via an RNA intermediate.
Its function is to code for rRNA.
Functionally important gene sequences such as those encoding ribosomal RNA are: Highly repetitive sequences. Minimally repetitive sequences. Moderately repetitive sequences. Transposable sequences. Highly mutated sequences.
Moderately repetitive sequences.
Homologous chromosomes pair with each other during meiosis, but are misaligned. What is the likely outcome if crossing over occurs? One daughter chromosome contains a gene duplication, the other three are normal. One daughter chromosome contains a gene deletion, the other three are normal. Two daughter chromosomes contain a gene duplication, the other two are normal. Two daughter chromosomes contain a gene deletion, the other two are normal. One daughter chromosome contains a gene duplication, one contains a gene deletion, and the remaining two are normal.
One daughter chromosome contains a gene duplication, one contains a gene deletion, and the remaining two are normal.
Which of the following is TRUE regarding plasmids? Plasmids are small, usually a few thousand to ten thousand base pairs. Plasmids are linear. Plasmids are contained within the bacterial chromosome. Plasmids are rarely found in prokaryotes. Plasmids dominate in eukaryotes.
Plasmids are small, usually a few thousand to ten thousand base pairs.
Which of the following statements about the differences between prokaryotic and eukaryotic genomes is FALSE? Prokaryotic genomes are less complex than eukaryotic genomes. Prokaryotic genomes have centromeres, whereas eukaryotic genomes do not. Eukaryotic genomes have telomeres, whereas prokaryotic genomes do not. Prokaryotic genomes have one origin of replication, whereas eukaryotic genomes have multiple origins of replication. Chromosomes of prokaryotes have little repetitive DNA compared with chromosomes of eukaryotes.
Prokaryotic genomes have centromeres, whereas eukaryotic genomes do not.
If the nitrogenous bases of both a DNA transposon and a retroelement were tagged with fluorescent markers, what statement best describes the result after transposition of both types of TEs has occurred? The markers would be found at the new site of the DNA transposon, but not at the new site of the retroelement. The markers would be found at the new site of the retroelement, but not at the new site of the DNA transposon. The markers would be found at the new sites of the DNA transposon and the retroelement. The markers would be not be found at either new site.
The markers would be found at the new site of the DNA transposon, but not at the new site of the retroelement.
Which of the following statements is TRUE of highly repetitive sequences? They play a vital role in transcription. They play a vital role in translation. They can be found millions of times in a eukaryotic genome. They typically increase fitness of the organism. They typically decrease fitness of the organism.
They can be found millions of times in a eukaryotic genome.
Genome databases have been created for all of the following model organisms except? fruit fly mice humans bacteria alligator
alligator
A researcher runs a BLAST program comparing turkey phenylalanine hydroxylase, which functions in the metabolism of phenylalanine, with known database sequences. Which of the following should provide the closest match? green pufferfish zebrafish chicken orangutan fruit fly
chicken
14 homologous genes encoding globins (hemoglobin, myoglobin) in the human genome were originally derived from a single ancestor that duplicated 500-600 million years ago. Which term most adequately describes the relationship between these genes? sister chromatids gene family gene cluster moderately repetitive sequences highly repetitive sequences
gene family
How would you summarize the relationship between the relative size of a species' genome and its proteome? genome = proteome genome > proteome genome < proteome genome = proteome in eukaryotes; genome > proteome in prokaryotes genome > proteome in eukaryotes; genome = proteome in prokaryotes
genome < proteome
DNA can be found in all of the following cellular locations EXCEPT the mitochondria. chloroplast. nucleus. golgi apparatus. plasma membrane
golgi apparatus.
Small chromosomal duplications provide raw material for the addition of genes into a species' genome. These duplications create two or more copies of the same gene, where one or both of the genes can subsequently mutate. These genes are referred to as: sister chromatids. homologous chromosomes. homologous genes. transposable elements. duplicated chromosomes.
homologous genes.
Which pair of organisms would have the most homologous b-globin genes? dolphin and bumble bee catfish and crocodile snake and mouse frog and cheetah human and chimpanzee
human and chimpanzee
Which of the following protein-functional categories is mismatched? hexokinase-metabolic enzyme tubulin-structural protein insulin-motor protein hemoglobin-transport protein antibodies-protective protein
insulin-motor protein
What cell type would have a high concentration of metabolic enzymes? nerve cell mammary cell lung cell liver cell cartilage cell
liver cell
What is the most likely explanation of how 14 genes for globins, each specialized in their function (i.e., hemoglobin, myoglobin), arose in the genome of animals? misaligned crossover gene deletion gene mutation misaligned crossover and gene mutation misaligned crossover and gene deletion
misaligned crossover and gene mutation
What cell type would have a high concentration of motor proteins? liver cell mammary cell hormone-secreting cell muscle cell nerve cell
muscle cell
What must be provided to the BLAST program for identifying homologous sequences within the database? Nucleotide sequence Amino acid sequence Protein molecular weight Protein molecular weight or nucleotide sequence Nucleotide sequence or amino acid sequence
nucleotide sequence or amino acid sequence
Homologous genes in different species are called: analogs. paralogs. orthologs. dialogs. monologs.
orthologs.
According to the selfish DNA hypothesis, which symbiotic relationship most closely resembles that of transposable elements that move within the organism's genome without offering benefits to the organism? mutualism commensalisms parasitism competition neutralism
parasitism
Which of the following is a reversible post-translational covalent modification? phosphorylation acetylation disulfide bond formation phosphorylation and acetylation acetylation and disulfide bond formation
phosphorylation and acetylation
What nucleic acid is subject to alternative splicing? DNA rRNA pre-mRNA mRNA tRNA
pre-mRNA
What is required if a researcher wants to analyze genes in different species for their homologies? relatively short DNA sequences relatively short RNA sequences relatively long DNA sequences relatively short polypeptide sequences relative differences in a species' metabolomics
relatively long DNA sequences
Which of the following can help researchers determine if two genes are homologous to each other? Punnet square simple dot matrix quadratic equation polypeptide structure geometric analysis
simple dot matrix
What category of proteins facilitates the movement of ions and molecules across membranes? regulatory proteins protective proteins transport proteins cell-signaling proteins motor proteins
transport proteins
What genetic elements can foster the process of crossing over? RNA polymerase promoter elements enhancer elements transposable elements topoisomerase
transposable elements