Question 1

Which of the following is NOT a tetrapyrrole?

Accepted Answer

A)  cytochrome 
B)  chlorophyll 
C)  vitamin B12 
D)  tryptophan 
E)  hemoglobin 
A)  cytochrome 
B)  chlorophyll 
C)  vitamin B12 
D)  tryptophan 
E)  hemoglobin

Question 2

Briefly discuss how carbon molecules of different sizes can be made for biosynthesis. What else is needed and how is it obtained?

Accepted Answer

Molecules with varying numbers of carbon

Question 3

The structures marked with arrows in the photo below are ________ and are used to ________.

Accepted Answer

A)  polyhydroxyalkanoates; sequester reactions using bicarbonate or carbon dioxide and Rubisco 
B)  polyhydroxyalkanoates; store carbon for energy 
C)  carboxysomes; store carbon for energy 
D)  carboxysomes; sequester reactions using bicarbonate or carbon dioxide and Rubisco 
E)  heterocysts; sequester reactions using bicarbonate or carbon dioxide and Rubisco 
A)  polyhydroxyalkanoates; sequester reactions using bicarbonate or carbon dioxide and Rubisco 
B)  polyhydroxyalkanoates; store carbon for energy 
C)  carboxysomes; store carbon for energy 
D)  carboxysomes; sequester reactions using bicarbonate or carbon dioxide and Rubisco 
E)  heterocysts; sequester reactions using bicarbonate or carbon dioxide and Rubisco

Question 4

Which of the following is NOT correct regarding the biosynthesis of purines and pyrimidines?

Accepted Answer

A)  5-phosphoribosyl-1-pyrophosphate (PRPP) is a precursor to both purines and pyrimidines. 
B)  The pyrimidine ring is synthesized first and then linked to 5-phosphoribosyl-1-pyrophosphate. 
C)  The purine ring is built around the C1 of 5-phosphoribosyl-1-pyrophosphate. 
D)  Both purines and pyrimidines use inosine monophosphate as a precursor. 
E)  Both purines and pyrimidines are built by adding carbon components to ribose 5-phosphate. 
A)  5-phosphoribosyl-1-pyrophosphate (PRPP) is a precursor to both purines and pyrimidines. 
B)  The pyrimidine ring is synthesized first and then linked to 5-phosphoribosyl-1-pyrophosphate. 
C)  The purine ring is built around the C1 of 5-phosphoribosyl-1-pyrophosphate. 
D)  Both purines and pyrimidines use inosine monophosphate as a precursor. 
E)  Both purines and pyrimidines are built by adding carbon components to ribose 5-phosphate.

Question 5

In the mechanism of nitrogen reduction, ________ directly takes the place of the H₂ in the FeMo subunit of the enzyme nitrogenase.

Accepted Answer

A)  NH3 
B)  N2 
C)  HN=NH 
D)  H2N-NH2 
E)  NADPH 
A)  NH3 
B)  N2 
C)  HN=NH 
D)  H2N-NH2 
E)  NADPH

Question 6

Which of the following is NOT correct about fatty acid biosynthesis?

Accepted Answer

A)  It involves successive condensations of malonyl-ACP. 
B)  A dehydratase is used to generate an unsaturated bond. 
C)  It is regulated by the stringent response of carbon starvation. 
D)  NADPH is generally involved in hydrogenation. 
E)  Many single-component enzymes are involved. 
A)  It involves successive condensations of malonyl-ACP. 
B)  A dehydratase is used to generate an unsaturated bond. 
C)  It is regulated by the stringent response of carbon starvation. 
D)  NADPH is generally involved in hydrogenation. 
E)  Many single-component enzymes are involved.

Question 7

Describe how modular enzymes function in polyketide biosynthesis. Why might this be of use medically?

Accepted Answer

Modular enzymes consist of multiple modu

Question 8

What is the most sensitive method to determine the presence of an isotope such as ¹⁴C in a sample?

Accepted Answer

A)  nuclear magnetic resonance (NMR) spectroscopy 
B)  radioactive decay 
C)  mass spectroscopy 
D)  polymerase chain reaction 
E)  high-performance liquid chromatography 
A)  nuclear magnetic resonance (NMR) spectroscopy 
B)  radioactive decay 
C)  mass spectroscopy 
D)  polymerase chain reaction 
E)  high-performance liquid chromatography

Question 9

The incorporation of NH₄⁺ into 2-oxoglutarate is the first step in nitrogen assimilation in bacterial cells. This reaction is catalyzed by the enzyme ________ and produces ________.

Accepted Answer

A)  glutamate dehydrogenase (GDH); glutamate 
B)  glutamine synthase (GS); glutamine 
C)  glutamate synthase (GOGAT); glutamate 
D)  2-oxoglutarate aminase (2-O
A) ; glutamine 
E)  2-oxoglutarate dehydrogenase (2-ODH); glutamine 
A)  glutamate dehydrogenase (GDH); glutamate 
B)  glutamine synthase (GS); glutamine 
C)  glutamate synthase (GOGAT); glutamate 
D)  2-oxoglutarate aminase (2-O
A) ; glutamine 
E)  2-oxoglutarate dehydrogenase (2-ODH); glutamine

Question 10

How do cyanobacteria benefit from their heterocysts attracting heterotrophic bacteria?

Accepted Answer

Some cyanobacterial heterocysts leak org

Question 11

Briefly describe the biosynthetic pathway for arginine.

Accepted Answer

Arginine biosynthesis in bacteria is a c

Question 12

What types of bacteria perform the reductive pentose phosphate cycle to fix CO₂?

Accepted Answer

A)  cyanobacteria 
B)  purple phototrophs 
C)  lithotrophs 
D)  heterotrophs 
E)  methanogens 
A)  cyanobacteria 
B)  purple phototrophs 
C)  lithotrophs 
D)  heterotrophs 
E)  methanogens

Question 13

Which of the following statements is NOT true about Rubisco?

Accepted Answer

A)  It catalyzes the addition of CO2 to ribulose 1,5-bisphosphate. 
B)  It is present in all organisms that use the Calvin cycle to fix CO2. 
C)  It is found in the carboxysomes of autotrophic bacteria. 
D)  All species contain the same number of large and small subunits. 
E)  Its structure is highly conserved across bacterial groups and chloroplasts. 
A)  It catalyzes the addition of CO2 to ribulose 1,5-bisphosphate. 
B)  It is present in all organisms that use the Calvin cycle to fix CO2. 
C)  It is found in the carboxysomes of autotrophic bacteria. 
D)  All species contain the same number of large and small subunits. 
E)  Its structure is highly conserved across bacterial groups and chloroplasts.

Question 14

Denitrification is the

Accepted Answer

A)  conversion of nitrate or nitrite to N2 by anaerobic respirers. 
B)  oxidation of NH4+ to nitrate or nitrite by lithotrophs. 
C)  conversion of N2 to NH4+. 
D)  removal of nitro groups from organic molecules. 
E)  removal of amino groups from organic molecules. 
A)  conversion of nitrate or nitrite to N2 by anaerobic respirers. 
B)  oxidation of NH4+ to nitrate or nitrite by lithotrophs. 
C)  conversion of N2 to NH4+. 
D)  removal of nitro groups from organic molecules. 
E)  removal of amino groups from organic molecules.

Question 15

The most ancient CO₂ fixation pathway in methanogens is the

Accepted Answer

A)  reverse TCA cycle. 
B)  3-hydroxypropionate cycle. 
C)  Calvin cycle. 
D)  reductive acetyl-CoA pathway. 
E)  Krebs cycle. 
A)  reverse TCA cycle. 
B)  3-hydroxypropionate cycle. 
C)  Calvin cycle. 
D)  reductive acetyl-CoA pathway. 
E)  Krebs cycle.

Question 16

What kind of reaction is the formation of oxaloacetate from phosphoenolpyruvate?

Accepted Answer

A)  catabolic 
B)  anaplerotic 
C)  decarboxylation 
D)  dehydrogenation 
E)  co-factor induced 
A)  catabolic 
B)  anaplerotic 
C)  decarboxylation 
D)  dehydrogenation 
E)  co-factor induced

Question 17

Which of the following does NOT serve as an intermediate in the biosynthesis of amino acids?

Accepted Answer

A)  citrate 
B)  2-oxoglutarate 
C)  pyruvate 
D)  3-phosphoglycerate 
E)  pentose phosphate 
A)  citrate 
B)  2-oxoglutarate 
C)  pyruvate 
D)  3-phosphoglycerate 
E)  pentose phosphate

Question 18

Which of the following drugs is a nonribosomal peptide antibiotic?

Accepted Answer

A)  erythromycin 
B)  penicillin 
C)  tetracycline 
D)  vancomycin 
E)  ciprofloxacin 
A)  erythromycin 
B)  penicillin 
C)  tetracycline 
D)  vancomycin 
E)  ciprofloxacin

Question 19

The ________ pathway is utilized for carbon fixation in chloroplasts and cyanobacteria.

Accepted Answer

A)  acetyl-CoA 
B)  reverse tricarboxylic acid cycle 
C)  3-hydroxypropionate cycle 
D)  reductive pentose phosphate cycle 
E)  Krebs cycle 
A)  acetyl-CoA 
B)  reverse tricarboxylic acid cycle 
C)  3-hydroxypropionate cycle 
D)  reductive pentose phosphate cycle 
E)  Krebs cycle

Question 20

The enzyme that carries out this reaction shown in the diagram below is ________, and the end product is ________.

Accepted Answer

A)  3-phosphoglycerate synthetase; added to another carbon dioxide 
B)  3-phosphoglycerate synthetase; reduced to glyceraldehyde-3-phosphate 
C)  nitrogenase; reduced to glyceraldehyde-3-phosphate 
D)  Rubisco; reduced to glyceraldehyde-3-phosphate 
E)  Rubisco; added to another carbon dioxide 
A)  3-phosphoglycerate synthetase; added to another carbon dioxide 
B)  3-phosphoglycerate synthetase; reduced to glyceraldehyde-3-phosphate 
C)  nitrogenase; reduced to glyceraldehyde-3-phosphate 
D)  Rubisco; reduced to glyceraldehyde-3-phosphate 
E)  Rubisco; added to another carbon dioxide

Exam 15: Biosynthesis

Which of the following is NOT a tetrapyrrole?

Briefly discuss how carbon molecules of different sizes can be made for biosynthesis. What else is needed and how is it obtained?

The structures marked with arrows in the photo below are ________ and are used to ________.

Which of the following is NOT correct regarding the biosynthesis of purines and pyrimidines?

In the mechanism of nitrogen reduction, ________ directly takes the place of the H₂ in the FeMo subunit of the enzyme nitrogenase.

Which of the following is NOT correct about fatty acid biosynthesis?

Describe how modular enzymes function in polyketide biosynthesis. Why might this be of use medically?

What is the most sensitive method to determine the presence of an isotope such as ¹⁴C in a sample?

The incorporation of NH₄⁺ into 2-oxoglutarate is the first step in nitrogen assimilation in bacterial cells. This reaction is catalyzed by the enzyme ________ and produces ________.

How do cyanobacteria benefit from their heterocysts attracting heterotrophic bacteria?

Briefly describe the biosynthetic pathway for arginine.

What types of bacteria perform the reductive pentose phosphate cycle to fix CO₂?

Which of the following statements is NOT true about Rubisco?

Denitrification is the

The most ancient CO₂ fixation pathway in methanogens is the

What kind of reaction is the formation of oxaloacetate from phosphoenolpyruvate?

Which of the following does NOT serve as an intermediate in the biosynthesis of amino acids?

Which of the following drugs is a nonribosomal peptide antibiotic?

The ________ pathway is utilized for carbon fixation in chloroplasts and cyanobacteria.

The enzyme that carries out this reaction shown in the diagram below is ________, and the end product is ________.

Microbial Life: Origin and Discovery

Observing the Microbial Cell

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Viruses

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

Filters

The structures marked with arrows in the photo below are and are used to .

The incorporation of NH₄⁺ into 2-oxoglutarate is the first step in nitrogen assimilation in bacterial cells. This reaction is catalyzed by the enzyme and produces .

The enzyme that carries out this reaction shown in the diagram below is , and the end product is .