BSC 310 Test I
whether there will be a requirement or production of energy.
The change in Gibbs free energy for a particular reaction is MOST useful in determining
proteins.
The class of macromolecules in microorganisms that contributes MOST to biomass is
mRNA / tRNA
The codon on the ________ matches with the anticodon on the ________ to direct the addition of the correct amino acid to the growing polypeptide chain.
transcriptome.
The entire complement of RNA produced under a given set of conditions is called a(n)
energy and coenzyme production.
When compared with Bacteria, species of Archaea seem to devote a higher percentage of their genomes to genes encoding proteins involved in
green algae, certain nitrogen-fixing root nodule bacteria, and certain sulfate-reducing bacteria.
Martinus Beijerinck was the first to isolate
True
Metabolism is a unifying characteristic of all cellular organisms.
Unusual, but legitimate genes and non-coding RNA may be missed.
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?
significantly smaller
A plasmid differs from the bacterial chromosome in that it is __________.
codon.
A triplet of bases on an mRNA molecule is known as a(n)
The cell can synthesize multiple copies of a protein from a single piece of mRNA.
How do polysomes illustrate the energy efficiency of a cell?
required to transform all reactants into their reactive state.
Activation energy is the energy
cytochromes.
All of the following are non-protein electron carriers EXCEPT -FMNH2. -FADH2. -quinones. -cytochromes.
a polypeptide.
An open reading frame (ORF) encodes for
allows coordinated expression of multiple related genes in prokaryotes.
An operon is a useful genetic element, because it
cyanobacteria
Approximately two billion years ago, ________ were primarily responsible for initially oxygenating Earth.
nuclei and membrane-enclosed organelles
Archaea and Bacteria are unified as prokaryotes in lacking ________ which Eukarya contain, such as golgi.
pathogen present in all cases of disease; pathogen isolated in pure culture; pathogen able to infect healthy host; pathogen re-isolated
Arrange Koch's postulates in the correct order.
genome, transcriptome, proteome, metabolome
Arrange the following genetic components in the correct order.
anaerobes--> anoxygenic phototrophs--> oxygenic phototrophs--> aerobes--> multicellular organisms
Arrange the types of microorganism in the order they evolved on Earth.
False
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
bacteria / endosymbiosis
Chloroplasts and mitochondria originated from ________ by a process known as ________.
because both elements contain nonessential genes
Chromosomal islands are similar to plasmids __________.
True
Codon usage and even the genetic code itself varies from one organism to the next.
4th generation
Comparing the different generations of DNA sequencing, which would be most appropriate for a 10 Mbp piece of DNA that could not be fragmented?
5'-phosphate / 3'-hydroxyl
DNA replication always proceeds in only one direction because the ________ of the incoming nucleotide is attached to the free ________ of the growing DNA strand.
True
DNA replication involves the synthesis of RNA primers on both strands of the DNA.
primer / RNA
DNA replication is started with a(n) ________, which, in most cases, in vivo is a short stretch of ________.
major groove
DNA-binding proteins interact predominantly within which portion of a double-stranded DNA helix?
False
Depending on the particular metabolism of a bacterium, electron transport can be used to energize and rotate ATP synthase.
Eukaryotes have more introns in their chromosomes.
Determine why some prokaryotes have less DNA but more genes than eukaryotes.
Fermentation forms organic acids and takes place in the absence of oxygen, while respiration forms water and carbon dioxide in the presence of oxygen.
Distinguish how fermentation and respiration differ.
DNA ligase
During DNA replication Okazaki fragments are linked together by________, an enzyme that creates phosphodiester bonds between nicked fragments of DNA.
True
During the electron transport process, protons and electrons become physically separated in the cell membrane.
two / three
Each adenine-thymine base pair has ________ hydrogen bonds, while each guanine-cytosine base pair has ________ hydrogen bonds.
so that they can transport NADH out of the cell to the periplasm
Electron carriers used in electron transport chains are always found in membranes. Which one of the following statements is NOT a reason why electron transport chains are found in membranes?
analysis of ribosomal RNA
Explain how organisms are placed into the three major cell lineages or domains.
The sequences within the promoter region at -10 and -35 are the most important for recognition by the sigma subunit.
Explain why promoters for the same sigma subunit do not have identical sequences in all organisms.
light
Fourth-generation sequencing methods no longer use ________ to detect nucleotide incorporation.
False
Free-energy calculations are dependent on the rates of the reactions.
ATP; the fermentation products are waste products.
From the standpoint of the microorganism, in glycolysis the crucial product is
The organism lives in an environment rich in organic material, particularly amino acids and proteins.
Functional analysis of the genome of a prokaryote shows that 20% of the genome is for metabolism, 1 % biosynthesis of amino acids, 8% peptide ABC transporters, and 2% replication. What can you determine about the environment this organism lives in?
translation.
GTP provides energy for
duplicate genes are free to evolve into new genes
Gene duplication is essential to organisms because __________.
True
Genes for DNA replication and transcription make up only a small fraction of the typical prokaryotic genome.
annotation
Linking an ORF with a specific function is an example of gene
homologous / gene families
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 ________.
chromosomes.
Genes that encode polymerases, gyrases, ribosomal proteins, and other proteins essential to replication, transcription, and translation are present on
phospholipids
Genetic information in the cell is carried by information molecules, including all EXCEPT which of the following?
overlap of a large numbers of short sequences.
Genome assembly relies on
number of ORFs.
Genomes of species in both Bacteria and Archaea show a strong correlation between genome size and
True
Genomic analysis led to the discovery that pathogenic organisms often lack genes for amino acid biosynthesis.
TCAGGCT
Given the following DNA sequence (5' ( 3'), what would be the DNA sequence on the complementary strand (3' ( 5') of a double-stranded helix molecule? DNA sequence: AGTCCGA
False
Heme prosthetic groups are involved in electron transfer with quinones.
False
Heterotrophs need only a few more genes than autotrophs.
conjugation, transduction, and transformation
Horizontal gene flow can be accomplished in prokaryotes by __________.
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.
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?
True
If a substance is reduced, it gains electrons.
simultaneous reduction of a different compound will also occur, because electrons do not generally exist alone in solution.
If an oxidation reaction occurs
The amount of ATP would be reduced from a total of 38 ATP to 14 ATP.
If the citric acid cycle was interrupted after the reaction that forms citrate, predict how this would affect the total amount of ATP generated per glucose molecule.
exergonic and energy will be released.
If ΔG0' is negative, the reaction is
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.
In DNA replication in vivo, RNA primers are used. However, researchers use DNA primers instead in the lab because DNA primers are more stable. Why might this be the case?
DNA replication is semiconservative and each strand is copied simultaneously in opposite directions.
In DNA replication there are leading and lagging strands, because
this will be the strongest -10 promoter sequence
In E. coli, the consensus sequence for the Pribnow box (the -10 sequence) is TATAAT. Therefore, __________.
False
It is generally accepted that independent mutation rather than gene duplication is the mechanism for evolution of most new genes.
detect pathogens, analyze global gene expression, and detect unwanted food additives or substitutes.
Microarrays can be used to
3.8 to 3.9
Microbial cells first evolved on Earth approximately ________ billion years ago.
microorganisms in their natural environments.
Microbial ecology is the study of
kill all microbes in or on objects.
Microbial sterilization is used to
False
Microorganisms that grow in extreme environments typically contain larger genomes when compared to microbes that grow in non-extreme environments.
rapidly evolving species.
Mobile DNA elements are more common in the genomes of
transposable elements.
Most mobile DNA consists of
True
Most prokaryotic genomes are double-stranded circular DNA.
Each base is identified with a different fluorescent color.
Newer sequencing techniques require only one lane on an electrophoresis gel rather than four. How is this possible?
a high fidelity in the copying of DNA is necessary for good heredity
Proofreading of newly-synthesized DNA is important because __________.
True
Sergei Winogradsky worked with bacteria involved in cycling nitrogen and sulfur.
transcriptome.
RNA-Seq analysis is a method aimed at defining a(n)
microbial life existed for billions of years before plant and animal life.
Regarding early life on Earth...
develop the tuberculin test, formulate four postulates for definitively linking a specific microorganism to a specific disease, and use agar as a solidifying agent in growth media.
Robert Koch contributed to the field of microbiology by being the first person to
nonsense
Stop codons are also called ________ codons.
it condenses the DNA so that it can fit inside the cell.
Supercoiling is important for DNA structure, because
specific nucleotide sequences on the template strand.
Termination of RNA synthesis is ultimately determined by
miniaturization of reaction size and increased computer power.
The advantage(s) of second-generation DNA sequencing compared to the Sanger method are the result of
False
The bubonic plague was caused by Yersinia pestis, a highly pathogenic virus.
rRNA genes most closely related to Bacteria
The evolutionary origin of mitochondria is demonstrated by which of the following key genomic characteristics?
comparative genomics
The field of study that can reveal how genes function, reveal how organisms interact with the environment, and show evolutionary relationships is __________.
mold / Robert Hooke
The first documented description of a microorganism was of a ________ by ________.
Virus
The first genome sequenced was that of a
the ribosome binding site (RBS) on the mRNA binds to the 16S rRNA to begin the formation of the initiation complex
The first step of translation begins when __________.
False
The formation of new DNA does NOT require energy.
a way to increase the types of redox reactions that occur in the cell by acting as an intermediary between dissimilar compounds
The function of NAD+/NADH in the cell is best described as __________.
catalyze the formation of phosphodiester bonds between ribonucleotides.
The function of RNA polymerase is to
the addition of deoxynucleotides.
The function of the DNA polymerase is to catalyze
Each time a new base is added, an H+ is removed. A pH meter would record an increase in H+ concentration in the environment as a decrease in pH (greater acidity).
The ion torrent sequencing method uses "the world's smallest pH meter" to detect the addition of bases. What change related to pH would be measured?
True
The key characteristic of third-generation sequencing is the ability to sequence single molecules of DNA.
False
The largest cellular genomes belong to prokaryotes that are parasitic or pathogenic.
those involved in metabolism.
The most abundant genes in prokaryotic genomes are
2.
The net gain of ATP per molecule of glucose fermented is
True
The net result of electron transport is the generation of a pH gradient and an electrochemical potential across the membrane.
present in one or more strains of the same species.
The pan genome of a species is the genomic content that is
active site.
The portion of an enzyme to which substrates bind is referred to as the
tRNA
The process of synthesizing proteins involves translating one "language," nucleic acid sequences, into another "language," amino acid sequences. The cellular component that does the actual translating from codons to amino acids is the __________.
the difference in charge across the plasma membrane with protons outside the membrane
The proton motive force (PMF) is driven by __________.
the greater the change in free energy (ΔG0′), and the greater the energy released
The reduction potential (E0′) of a substance reflects its tendency to donate or accept electrons. The larger the difference (ΔE0′) between the reduction potentials of the electron donor and the electron acceptor, __________.
True
The relative percentage of genes devoted to protein synthesis in small-genome organisms is high compared with that of large-genome organisms.
With the replisome, it can replicate both strands of DNA at the same time.
The replisome is a large complex of proteins that contains many enzymes involved in DNA replication. Hypothesize why these enzymes do NOT function independently of each other.
bioinformatics
The science that applies powerful computational tools to DNA and protein sequences for the purpose of analyzing, storing, and accessing the sequences for comparative purposes is known as
amino acid
The structure and function of a protein are determined by its ________ sequence.
DNA / antiparallel and complementary
The template for RNA polymerase is ________, and the new RNA chain is ________ to the template.
hydrogen bonds between nucleotide bases.
The two strands of the DNA double helix are held together by
the incorporation of dideoxynucleotides that terminate chain extension during DNA synthesis.
The very first DNA sequencing technology called the Sanger method relies on
Coenzymes are weakly bound whereas prosthetic groups are strongly bound to their respective enzymes.
What is the difference between a coenzyme and a prosthetic group?
True
Throughout the living world, the genetic code is generally universal; however, there are slight variations.
The reaction will be exergonic.
To calculate the free energy (ΔG0′) of a reaction, you can subtract the free energies of formation (Gf0) of the reactants from those of the products. Given the following data, what will be true of this reaction? C6H12O6 + O2 → CO2 + H2O Gf0 : -917.3 0 -394.4 -237.2
a start codon and a ribosomal binding site (RBS)
To determine if you have identified a functional open reading frame (ORF), you should have found within the sequence __________.
it analyzes RNA, thus it reveals which genes are expressed under different conditions.
Transcriptome analysis is useful in relation to genome analysis because
function to transfer the correct amino acids to the ribosome during translation.
Transfer RNA molecules
segments of DNA that move from one site to another.
Transposable elements are
30 %
Typically ________ of ORFs in a genome cannot clearly be assigned a function. These ORFs are usually assigned and predicted to encode hypothetical proteins.
True
Varied coenzyme availability increases the diversity of enzymatic reactions in both biosynthetic and catabolic pathways possible in a cell.
developed enrichment culture techniques
Which of the following is NOT an accomplishment of Louis Pasteur? -developed enrichment culture techniques -developed heat sterilization techniques that involved the creation of a specialized swan-necked flask -determined that the alcohol-making process was mediated by microbial fermentation and thus refuted the theory of spontaneous generation -developed the first rabies vaccine and treated thousands of individuals
Both processes require an RNA primer to begin.
Which of the following is NOT correct regarding DNA and RNA synthesis?
CAG
Which of the following is an example of one codon?
Okazaki fragments
Which of the following is formed on the lagging strand during DNA synthesis?
Microbial cells include both bacteria and viruses.
Which of the following statements is FALSE? -Microbial cells exist as single cells. -Microbial cells exclude the cells of plants and animals. -Microbial cells include both bacteria and viruses. -Microbial cells carry out their life processes of growth independently.
mRNA has a very short half-life.
Which of the following statements is TRUE concerning mRNA?
a yeast cell
Which of these organisms is likely to have the largest genome? -a chloroplast -an autotrophic bacterium -an extremophile Archaean due to the demands of surviving in harsh environments -a yeast cell
several genes, next to each other in prokaryotic DNA, that are transcribed as a single piece of mRNA
Which statement best describes an operon?
The rRNA recognizes the correct start codon with the aid of an upstream Shine-Dalgarno sequence.
Which statement illustrates how prokaryotes determine where to begin translation so the correct protein is synthesized?
The 23S rRNA catalyzes peptide bond formation in the growing polypeptide chain.
Which statement is TRUE regarding protein synthesis?
True
rRNA has an enzymatic role in all stages of protein synthesis.
E
tRNA is released from the ribosome at the ________ site.
1,000
Within Archaea and Bacteria, one megabasepairs of DNA encode about ________ open reading frames.
make direct observations of microbes
Although the existence of microorganisms was surmised long before, their discovery depended upon a technological development (the microscope) in order for scientists to __________.
True
Aminoacyl-tRNA synthetase catalyzes the reaction between the appropriate amino acid and ATP to form an activated amino acid: amino acid + ATP ↔ aminoacyl-AMP + P-P.
primers or nucleotides that will be incorporated into the newly synthesized DNA
In Sanger sequencing and in many newer sequencing techniques, labeled precursors are used. What are these precursors?
oxygen.
In aerobic respiration, the final electron acceptor is
a protein, tRNA, or rRNA depending on the specific gene.
In all cells a gene encodes for
endosymbiont
In general, prokaryotic genome size is correlated to lifestyle. Which type of prokaryote typically has the smallest genome?
True
In nature, the predominant form of DNA is supercoiled in a negative direction.
It is the nucleotide most commonly found at a particular location.
In sequencing, it may be necessary to find a consensus nucleotide. What does this mean?
DNA / sigma factors
In the process of transcription, promoters are specific sequences of ________ that are recognized by ________.
Archaea, Bacteria, and Eukarya
In what/which domain(s) of life is/are microorganisms represented?
fermentation
Which metabolic strategy does NOT utilize the proton motive force? -aerobic respiration -photosynthesis -fermentation -anaerobic respiration
DNA polymerase requires a free 3′-hydroxyl group to add nucleotides.
Which statement illustrates why DNA polymerase cannot initiate a new DNA strand?
a single piece of mRNA that contains the transcript for multiple genes.
Which statement is the correct definition of polycistronic mRNA?
Organisms with very small genomes tend to have essential genes with minimal additional material.
Why is having few or no inteins related to having a very small genome?
True
With the replisome, it can replicate both strands of DNA at the same time.
The DNA sequence likely functions as a ribosome-binding site.
You experimentally change the DNA sequence directly upstream of a start codon of an operon in E. coli to investigate the function of this region of DNA. Analysis reveals that after the change the same amount of mRNA is made from the operon, but there are very few proteins made from the operon. What is the most likely function of the DNA sequence that you changed?
Robert Hooke / Antoni van Leeuwenhoek
________ was the first to describe microorganisms, while ________ was the first person to see bacteria.