Question 1

Explain why recA, the gene encoding recombinase enzyme in Bacteria, is not used in evolutionary studies.

Accepted Answer

The recA gene has a highly conserved nucleotide sequence. Because its nucleotide sequence is very similar throughout Bacteria, there are not enough differences to merit it a useful phylogenetic marker.

Question 2

In doing comparative SSU rRNA sequencing, it is essential that pure (axenic) cultures be used.

Accepted Answer

A) True 
 B)False  False

Question 3

A monophyletic group is a group that

Accepted Answer

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

Question 4

Explain why in both taxonomy and phylogeny the reliance on the sequence of a single gene can have pitfalls.

Accepted Answer

Using one gene for phylogenetics can be

Question 5

As oxygen appeared in the atmosphere, some of it accumulated in the form of________ , which formed a protective barrier that prevents________ from reaching Earth.

Accepted Answer

ozone / UV

Question 6

What two gases were most abundant on early Earth?

Accepted Answer

A)  CO2 and N2 
B)  CO2and H2 
C)  CH4 and H2 
D)  CH4 and CO2 
A)  CO2 and N2 
B)  CO2and H2 
C)  CH4 and H2 
D)  CH4 and CO2

Question 7

The domains arose as barriers between evolved organisms.

Accepted Answer

A) True 
 B)False

Question 8

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

The answer of One widely used cladistic method of examining...

Question 9

T- RFLP is a molecular technique often applied for phylogenetic analyses of microbial communities.

Accepted Answer

A) True 
 B)False

Question 10

Hybridization values of 50% or greater are recommended for considering two isolates to be of the same species.

Accepted Answer

A) True 
 B)False

Question 11

Fossilized microbial mats consisting of layers of filamentous prokaryotes and trapped sediment are known as________ .

Accepted Answer

The answer of Fossilized microbial mats consisting of layers of...

Question 12

Describe the hydrogen hypothesis and why it is favored over other hypotheses.

Accepted Answer

The hydrogen hypothesis states that a hy

Question 13

Oxygen did not accumulate in the early atmosphere until it reacted with reduced materials, especially________ , in the oceans. These substances then reacted spontaneously with oxygen to produce________.

Accepted Answer

The answer of Oxygen did not accumulate in the early...

Question 14

RDP- II is the standard abbreviation of _________ .

Accepted Answer

Ribosomal

Question 15

None of the organisms living today are primitive.

Accepted Answer

A) True 
 B)False

Question 16

Using present terminology, how many bacterial phyla have been discovered thus far?

Accepted Answer

A)  8, but the actual number may be as high as 25 
B)  4, but the actual number may be as high as 10 
C)  40, but the actual number may be higher 
D)  at least 80 
A)  8, but the actual number may be as high as 25 
B)  4, but the actual number may be as high as 10 
C)  40, but the actual number may be higher 
D)  at least 80

Question 17

Explain how gene duplication can lead to new functions in haploids.

Accepted Answer

Haploid microorganisms that ha

Question 18

The most widely used molecule in sequence- based evolutionary analyses are________ genes.

Accepted Answer

A)  SSU rRNA 
B)  ATPase 
C)  18S rRNA 
D)  electron transport 
A)  SSU rRNA 
B)  ATPase 
C)  18S rRNA 
D)  electron transport

Question 19

Evolution is driven by

Accepted Answer

A)  selection pressure. 
B)  the creation of novel metabolic pathways. 
C)  mutation. 
D)  both A and C. 
A)  selection pressure. 
B)  the creation of novel metabolic pathways. 
C)  mutation. 
D)  both A and C.

Question 20

Compared with today, the temperature on Earth during its first half- billion years was probably

Accepted Answer

A)  considerably colder. 
B)  about the same as today. 
C)  considerably warmer. 
D)  about the same as today on average, but the diurnal fluctuations were much greater. 
A)  considerably colder. 
B)  about the same as today. 
C)  considerably warmer. 
D)  about the same as today on average, but the diurnal fluctuations were much greater.

Exam 16: Microbial Evolution and Systematics

Explain why recA, the gene encoding recombinase enzyme in Bacteria, is not used in evolutionary studies.

In doing comparative SSU rRNA sequencing, it is essential that pure (axenic) cultures be used.

A monophyletic group is a group that

Explain why in both taxonomy and phylogeny the reliance on the sequence of a single gene can have pitfalls.

As oxygen appeared in the atmosphere, some of it accumulated in the form of________ , which formed a protective barrier that prevents________ from reaching Earth.

What two gases were most abundant on early Earth?

The domains arose as barriers between evolved organisms.

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.

T- RFLP is a molecular technique often applied for phylogenetic analyses of microbial communities.

Hybridization values of 50% or greater are recommended for considering two isolates to be of the same species.

Fossilized microbial mats consisting of layers of filamentous prokaryotes and trapped sediment are known as________ .

Describe the hydrogen hypothesis and why it is favored over other hypotheses.

Oxygen did not accumulate in the early atmosphere until it reacted with reduced materials, especially________ , in the oceans. These substances then reacted spontaneously with oxygen to produce________.

RDP- II is the standard abbreviation of _________ .

None of the organisms living today are primitive.

Using present terminology, how many bacterial phyla have been discovered thus far?

Explain how gene duplication can lead to new functions in haploids.

The most widely used molecule in sequence- based evolutionary analyses are________ genes.

Evolution is driven by

Compared with today, the temperature on Earth during its first half- billion years was probably

Microorganisms and Microbiology

A Brief Journey to the Microbial World

Cell Structure and Function in Bacteria and Archaea

Nutrition, Culture, and Metabolism of Microorganisms

Microbial Growth

Molecular Biology of Bacteria

Archael and Eukaryotic Molecular Biology

Regulation of Gene Expression

Viruses and Virology

Genetics of Bacteria and Arachaea

Genetic Engineering

Microbial Genomics

Phototrophy, Chemolithotrophy, and Major Biosyntheses

Catabolism of Organic Compounds

Commercial Products and Biotechnology

Bacteria: the Proteobacteria

Other Bacteria

Archaea

Eukaryotic Cell Biology and Eukaryotic Microorganisms

Viral Diversity

Methods in Microbial Ecology

Major Microbial Habitats and Diversity

Nutrient Cycles, Biodegradation, and Bioremediation

Microbial Symbioses

Microbial Growth Control

Microbial Interactions With Humans

Immunity and Host Defense

Immune Mechanisms

Molecular Immunology

Diagnostic Microbiology and Immunology

Epidemiology

Person-To-Person Microbial Diseases

Vectorborne and Soilborne Microbial Pathogens

Wastewater Treatment, Water Purification, and Waterborne Microbial Diseases

Food Preservation and Foodborne Microbial Diseases

Filters

As oxygen appeared in the atmosphere, some of it accumulated in the form of , which formed a protective barrier that prevents from reaching Earth.

Oxygen did not accumulate in the early atmosphere until it reacted with reduced materials, especially , in the oceans. These substances then reacted spontaneously with oxygen to produce.