Question 1

The hyperthermophilic members of the Crenarchaeota branch very close to the root of the universal tree.

Accepted Answer

A) True 
 B)False  True

Question 2

Explain the strengths and limitations of using 16S rRNA for phylogenetic analyses.

Accepted Answer

Due to function constraints,the 16S rRNA gene sequence has changed relatively little over time and is therefore an excellent individual nucleotide sequence useful in phylogenetic studies.It is not especially good at distinguishing among different species within a genus,because there is often not enough variation between the sequences.There are large and freely available databases dedicated to cataloging 16S rDNA sequences,and it remains the "gold standard" today for phylogenetic analyses.

Question 3

Because DNA:DNA hybridization reveals subtle differences in genes,it is useful for differentiating organisms from different

Accepted Answer

A) domains. 
B) families. 
C) orders. 
D) strains or species. 
A) domains. 
B) families. 
C) orders. 
D) strains or species. D

Question 4

One widely used cladistic method of examining evolutionary relationships is ________,which is based on the assumption that evolution is most likely to have proceeded by the path requiring fewest changes.

Accepted Answer

A) topology 
B) neighbor joining 
C) parsimony 
D) systematics 
A) topology 
B) neighbor joining 
C) parsimony 
D) systematics

Question 5

A monophyletic group is a group that

Accepted Answer

A) descended from one ancestor. 
B) has the same fitness level. 
C) possesses one taxonomic trait that is the same. 
D) shares one phylogenetic marker. 
A) descended from one ancestor. 
B) has the same fitness level. 
C) possesses one taxonomic trait that is the same. 
D) shares one phylogenetic marker.

Question 6

Molecular sequencing suggests that mitochondria arose from a group of prokaryotic organisms within the

Accepted Answer

A) Crenarchaeota. 
B) cyanobacteria. 
C) iron-oxidizing bacteria. 
D) Proteobacteria. 
A) Crenarchaeota. 
B) cyanobacteria. 
C) iron-oxidizing bacteria. 
D) Proteobacteria.

Question 7

Evolution is driven by

Accepted Answer

A) random mutation. 
B) novel metabolic pathways. 
C) selection pressure. 
D) selection pressure applied to random mutation. 
A) random mutation. 
B) novel metabolic pathways. 
C) selection pressure. 
D) selection pressure applied to random mutation.

Question 8

Oxygen did not accumulate in the early atmosphere until it reacted with reduced materials,especially ________,in the oceans.

Accepted Answer

A) hydrogen 
B) elemental sulfur 
C) ferrous iron 
D) nitrate 
A) hydrogen 
B) elemental sulfur 
C) ferrous iron 
D) nitrate

Question 9

Carl Woese was an important figure in microbial classification and changed our understanding of the evolution and diversity of life.What breakthrough did he make that allowed us to infer evolutionary relationships between organisms? What assumptions was his breakthrough based on?

Accepted Answer

During the 1970s,Dr.Carl Woese pioneered

Question 10

Microbial species are difficult to define because they are often polyphyletic.

Accepted Answer

A) True 
 B)False

Question 11

Eukaryotes originated after the rise in atmospheric oxygen.

Accepted Answer

A) True 
 B)False

Question 12

Why is the biological species concept useful for Eukarya but not meaningful for Archaea and Bacteria? How are prokaryotic species defined?

Accepted Answer

A species is an interbreeding population

Question 13

The first catalytic and self-replication biological molecule was most likely

Accepted Answer

A) RNA. 
B) DNA. 
C) proteins. 
D) ATP. 
A) RNA. 
B) DNA. 
C) proteins. 
D) ATP.

Question 14

Based on the phylogenetic tree below,which of the following statements is FALSE?

Accepted Answer

A) Species E is more closely related to species A than to species D. 
B) Species D is more closely related to species C than to species E. 
C) Species F is more closely related to species D than to species E. 
D) Species C is more closely related to species B than to species D. 
A) Species E is more closely related to species A than to species D. 
B) Species D is more closely related to species C than to species E. 
C) Species F is more closely related to species D than to species E. 
D) Species C is more closely related to species B than to species D.

Question 15

Construct a chart to demonstrate the molecular features of the primary domains of life.Why are there overlapping or shared molecular features between all three domains? Relate the shared and unique molecular features of each domain to early evolution,the last universal common ancestor (LUCA),and the evolution of the three domains

Accepted Answer

Answers should include some of the infor

Question 16

The early energy reactions used hydrogen,which is a powerful ________ and could have been used to form ________.

Accepted Answer

A) oxidant / the proton motive force 
B) electron donor / the proton motive force 
C) electron acceptor / oxygen 
D) oxidant / oxygen 
A) oxidant / the proton motive force 
B) electron donor / the proton motive force 
C) electron acceptor / oxygen 
D) oxidant / oxygen

Question 17

What characteristics make a gene a good candidate for determining the evolutionary relationships between organisms?

Accepted Answer

A) highly conserved 
B) universally distributed 
C) transferred horizontally between species 
D) highly conserved and universally distributed 
A) highly conserved 
B) universally distributed 
C) transferred horizontally between species 
D) highly conserved and universally distributed

Question 18

Microbial species have a core genome and a pan genome.What is the difference between the two?

Accepted Answer

A) The core genome consists of all the nucleic acid polymerases and translation enzymes,while the pan genome consists of all the biosynthetic pathways. 
B) The core genome is the set of genes within the mitochondria,while the pan genome is the set of genes in the nucleus of a species. 
C) The core genome is a set of genes shared by all members of a species,while the pan genome includes the core genes as well as genes that are not shared by all members. 
D) The core genome is the set of genes introduced by horizontal gene transfer,while the pan genome is the set of genes that is not transferred horizontally. 
A) The core genome consists of all the nucleic acid polymerases and translation enzymes,while the pan genome consists of all the biosynthetic pathways. 
B) The core genome is the set of genes within the mitochondria,while the pan genome is the set of genes in the nucleus of a species. 
C) The core genome is a set of genes shared by all members of a species,while the pan genome includes the core genes as well as genes that are not shared by all members. 
D) The core genome is the set of genes introduced by horizontal gene transfer,while the pan genome is the set of genes that is not transferred horizontally.

Question 19

Draw a graph of relative fitness and number of mutations of an evolving strain versus the ancestral strain over 20,000 generations under the same growth conditions.Explain the change in fitness and mutations over time using evolutionary concepts and terms.

Accepted Answer

The graph should show an initial rapid i

Question 20

Ribotyping

Accepted Answer

A) bypasses sequencing and sequence alignments. 
B) exploits unique DNA restriction patterns. 
C) allows discrimination between species and different strains of a species. 
D) bypasses sequencing and sequence alignments,exploits unique DNA restriction patterns,and allows discrimination between species and different strains of a species. 
A) bypasses sequencing and sequence alignments. 
B) exploits unique DNA restriction patterns. 
C) allows discrimination between species and different strains of a species. 
D) bypasses sequencing and sequence alignments,exploits unique DNA restriction patterns,and allows discrimination between species and different strains of a species.

Exam 12: Microbial Evolution and Systematics

The hyperthermophilic members of the Crenarchaeota branch very close to the root of the universal tree.

Explain the strengths and limitations of using 16S rRNA for phylogenetic analyses.

Because DNA:DNA hybridization reveals subtle differences in genes,it is useful for differentiating organisms from different

One widely used cladistic method of examining evolutionary relationships is ________,which is based on the assumption that evolution is most likely to have proceeded by the path requiring fewest changes.

A monophyletic group is a group that

Molecular sequencing suggests that mitochondria arose from a group of prokaryotic organisms within the

Evolution is driven by

Oxygen did not accumulate in the early atmosphere until it reacted with reduced materials,especially ________,in the oceans.

Carl Woese was an important figure in microbial classification and changed our understanding of the evolution and diversity of life.What breakthrough did he make that allowed us to infer evolutionary relationships between organisms? What assumptions was his breakthrough based on?

Microbial species are difficult to define because they are often polyphyletic.

Eukaryotes originated after the rise in atmospheric oxygen.

Why is the biological species concept useful for Eukarya but not meaningful for Archaea and Bacteria? How are prokaryotic species defined?

The first catalytic and self-replication biological molecule was most likely

Based on the phylogenetic tree below,which of the following statements is FALSE?

The early energy reactions used hydrogen,which is a powerful ________ and could have been used to form ________.

What characteristics make a gene a good candidate for determining the evolutionary relationships between organisms?

Microbial species have a core genome and a pan genome.What is the difference between the two?

Draw a graph of relative fitness and number of mutations of an evolving strain versus the ancestral strain over 20,000 generations under the same growth conditions.Explain the change in fitness and mutations over time using evolutionary concepts and terms.

Ribotyping

Microorganisms and Microbiology

Microbial Cell Structure and Function

Microbial Metabolism

Molecular Biology

Microbial Growth and Control

Microbial Genomics

Metabolic Regulation

Viruses and Virology

Viral Genomes and Diversity

Genetics of Bacteria and Archaea

Genetic Engineering and Biotechnology

Metabolic Diversity of Microorganisms

Functional Diversity of Bacteria

Diversity of Bacteria

Diversity of Archaea

Diversity of Eukaryotic Microorganisms

Methods in Microbial Ecology

Microbial Ecosystems

Nutrient Cycles

Microbiology of the Built Environment

Microbial Symbioses

Microbial Interactions With Humans

Immunity and Host Defense

Immune Mechanisms

Molecular Immunology

Diagnostic Microbiology

Epidemiology

Person-To-Person Bacterial and Viral Diseases

Vectorborne and Soilborne Bacterial and Viral Diseases

Water and Food As Vehicles of Bacterial Diseases

Eukaryotic Pathogens: Fungal and Parasitic Diseases

Filters

The early energy reactions used hydrogen,which is a powerful and could have been used to form .