©FYNDLAY.
MCB6937 Exam 2 Questions And Answers
100% Verified.
Define thermodynamics. List the laws of thermodynamic and describe their relevance in the
chemical reactions. What "life obeys laws of thermodynamic" means? -
Answers✔Thermodynamics: Energy change in a system
1st Law: energy is not created nor destroyed
- so total Energy is constant
2nd Law: entropy (disorder) is constantly increasing
quote meaning: without the energy input, life could not exist. life is able to persist in an ordered
fashion because it uses energy from the environment and releases heat, thereby increasing
disorder in the universe as a whole
Define the standard reduction potential. Why aerobic grow generates the highest amount of
energy (ATP). How this value plays a role in organization of electron transport system. -
Answers✔
Compare E'0 of aerobic and anaerobic respiration. - Answers✔
True or False: A redox pair with more negative reduction potential will spontaneously donate
electrons to a pair with more positive potential. - Answers✔
True or False: The first electron carrier in an ETC has the most negative E'0 - Answers✔
True or False: The more positive the reduction potentials, the greater the affinity for electrons. -
Answers✔
True or False: ETC are associated with plasma membranes or mitochondrial/chloroplast internal
membranes - Answers✔
True or False: All molecules found in ETC are capable of transferring both electrons and protons
- Answers✔
1
, ©FYNDLAY.
Describe the flow of electron in fermentation and respiration. What happened to the electron in
each of the above processes (final electron acceptor?) - Answers✔
Describe how enzymes are involved in chemical reactions: activation energy, lowering E -
Answers✔They carry out reactions
Speed up reaction rate (decrease energy required) to get to equilibrium more quickly
- protein catalysts
- high specificity
- not altered in reaction
Substrates = reacting molecules
Products = substances formed by reaction
Define apoenzyme, cofactor, and prosthetic group. What is the significance of cofactors? -
Answers✔Apoenzyme: protein component of enzyme
Cofactor: NONprotein component
- prosthetic group: firmly attached
- (coenzyme: loosely attached; are usually carriers)
How enzymatic activities are regulated or inhibited. - Answers✔Enzyme Regulation
- Post-transitional
- two key reversible control measures
1)allosteric regulation: adding to protein
2)covalent modification: permanently modifying
protein
Enzyme inhibition
- Competitive
- competes with binding of substrate to active site
- which can be overcome by adding substrate
2
, ©FYNDLAY.
- NONcompetitive
- binds enzyme at site OTHER than active site
- changes enzyme's shape ==> less active
- canNOT be overcome by adding substrate
How use of Sulfanilamide uses competitive inhibition to control enzymes involved in synthesis
of folic acid (Figures 10.17) - Answers✔
What is the role of prosthetic groups? - Answers✔
Compare and contrast ribozymes and enzymes/ What are they made of? Describe the role of
ribozymes in self-splicing. (Table 10.4) - Answers✔
Distinguish allosteric regulation and covalent modification - Answers✔
List and describe effects of environmental factors on enzymatic activities. How? - Answers✔
What chemical intermediate links pyruvate to TCA cycle? - Answers✔
Compare respiration and fermentation. Why anaerobic respiration and fermentation make less
ATP than aerobic respiration? - Answers✔
Do any of the eukaryotes perform fermentation? Give examples - Answers✔
List the three chemoorganotrophic fueling processes. - Answers✔
What are the important features of Chemoorganotrophs? Can they use the same compound as a C
source, energy source, and as a source for reducing power? Give an example. - Answers✔
What is meant by CO2 fixation? List three pathways used by microbes to fix CO2 - Answers✔
List groups of organisms based on their energy source, carbon source and the source of electron -
Answers✔Energy Source:
- chemoorganotrophs: organic molecules
- chemolithotrophs: inorganic molecules
- phototrophs: light
Carbon Source:
- Autotroph: CO2
- Heterotroph: organic molecules
3
MCB6937 Exam 2 Questions And Answers
100% Verified.
Define thermodynamics. List the laws of thermodynamic and describe their relevance in the
chemical reactions. What "life obeys laws of thermodynamic" means? -
Answers✔Thermodynamics: Energy change in a system
1st Law: energy is not created nor destroyed
- so total Energy is constant
2nd Law: entropy (disorder) is constantly increasing
quote meaning: without the energy input, life could not exist. life is able to persist in an ordered
fashion because it uses energy from the environment and releases heat, thereby increasing
disorder in the universe as a whole
Define the standard reduction potential. Why aerobic grow generates the highest amount of
energy (ATP). How this value plays a role in organization of electron transport system. -
Answers✔
Compare E'0 of aerobic and anaerobic respiration. - Answers✔
True or False: A redox pair with more negative reduction potential will spontaneously donate
electrons to a pair with more positive potential. - Answers✔
True or False: The first electron carrier in an ETC has the most negative E'0 - Answers✔
True or False: The more positive the reduction potentials, the greater the affinity for electrons. -
Answers✔
True or False: ETC are associated with plasma membranes or mitochondrial/chloroplast internal
membranes - Answers✔
True or False: All molecules found in ETC are capable of transferring both electrons and protons
- Answers✔
1
, ©FYNDLAY.
Describe the flow of electron in fermentation and respiration. What happened to the electron in
each of the above processes (final electron acceptor?) - Answers✔
Describe how enzymes are involved in chemical reactions: activation energy, lowering E -
Answers✔They carry out reactions
Speed up reaction rate (decrease energy required) to get to equilibrium more quickly
- protein catalysts
- high specificity
- not altered in reaction
Substrates = reacting molecules
Products = substances formed by reaction
Define apoenzyme, cofactor, and prosthetic group. What is the significance of cofactors? -
Answers✔Apoenzyme: protein component of enzyme
Cofactor: NONprotein component
- prosthetic group: firmly attached
- (coenzyme: loosely attached; are usually carriers)
How enzymatic activities are regulated or inhibited. - Answers✔Enzyme Regulation
- Post-transitional
- two key reversible control measures
1)allosteric regulation: adding to protein
2)covalent modification: permanently modifying
protein
Enzyme inhibition
- Competitive
- competes with binding of substrate to active site
- which can be overcome by adding substrate
2
, ©FYNDLAY.
- NONcompetitive
- binds enzyme at site OTHER than active site
- changes enzyme's shape ==> less active
- canNOT be overcome by adding substrate
How use of Sulfanilamide uses competitive inhibition to control enzymes involved in synthesis
of folic acid (Figures 10.17) - Answers✔
What is the role of prosthetic groups? - Answers✔
Compare and contrast ribozymes and enzymes/ What are they made of? Describe the role of
ribozymes in self-splicing. (Table 10.4) - Answers✔
Distinguish allosteric regulation and covalent modification - Answers✔
List and describe effects of environmental factors on enzymatic activities. How? - Answers✔
What chemical intermediate links pyruvate to TCA cycle? - Answers✔
Compare respiration and fermentation. Why anaerobic respiration and fermentation make less
ATP than aerobic respiration? - Answers✔
Do any of the eukaryotes perform fermentation? Give examples - Answers✔
List the three chemoorganotrophic fueling processes. - Answers✔
What are the important features of Chemoorganotrophs? Can they use the same compound as a C
source, energy source, and as a source for reducing power? Give an example. - Answers✔
What is meant by CO2 fixation? List three pathways used by microbes to fix CO2 - Answers✔
List groups of organisms based on their energy source, carbon source and the source of electron -
Answers✔Energy Source:
- chemoorganotrophs: organic molecules
- chemolithotrophs: inorganic molecules
- phototrophs: light
Carbon Source:
- Autotroph: CO2
- Heterotroph: organic molecules
3
