BS 161 Exam 2 Questions with verified answers
_____ are organisms that derive energy from sunlight. Ans✓✓✓ Phototrophs
A protein that is temporarily associated with a biological membrane is a(n):
Ans✓✓✓ peripheral membrane protein.
Based on the information gained while completing the modeling activity in class,
which of the following changes would most likely result in weight loss? Ans✓✓✓
an increase in the ratio of NAD+/NADH and FADH/FADH2
Carbon atoms that entered glycolysis as glucose will enter the Kerbs cycle as
______ and leave the Krebs cycle as______. Ans✓✓✓ acetyl-CoA; CO2
Cellular respiration is a series of _____ reactions. Ans✓✓✓ catabolic
Cellular respiration releases energy. In cellular respiration: Ans✓✓✓ the chemical
potential energy stored in organic molecules is converted to chemical energy that
can be used to do the work of the cell.
Complete oxidation of glucose to CO2 involves two different mechanisms for
synthesizing ATP: oxidative phosphorylation and substrate-level phosphorylation.
What is TRUE of substrate-level phosphorylation? Ans✓✓✓ An enzyme catalyzes
the transfer of a phosphate group to ADP from an organic molecule to form ATP
Disorders of which organelle are often associated with defects in transport from
compartment to compartment, resulting in poor sorting of protein components
within the cell? Ans✓✓✓ The Golgi Apparatus
,During cellular respiration, what is the fate of the NADH generated by the citric
acid cycle Ans✓✓✓ It is oxidized to NAD+ to power the mitochondrial electron
transport chain.
During glycolysis, a phosphate is transferred from 1,3-bisphosphoglycerate to
ADP. This illustrates what type of process? Ans✓✓✓ substrate-level
phosphorylation
During the citric acid cycle Ans✓✓✓ ATP is synthesized by substrate-level
phosphorylation
During the translation of mRNA molecules, the new polypeptides are often
directed to specific parts of the cell by the presence or absence of short
sequences of amino acids called signal peptides. What would you expect to find in
the polypeptide that will eventually fold to become a transmembrane protein?
Ans✓✓✓ an ER signal peptide and a signal anchor peptide
Electrons enter the electron transport chain at either complex I or II. Electrons
entering through complex I are donated by: Ans✓✓✓ NADH
Energy released by transferring electrons along the electron transport chain is
stored as potential energy in the form of: Ans✓✓✓ a proton gradient
Entropy is often increased by: Ans✓✓✓ Heat
Excess glucose is stored in large branched molecules of: Ans✓✓✓ glycogen in
animals.
, Following oxidation of glucose by glycolysis, the pyruvate dehydrogenase
complex, and the TCA cycle, but prior
to the use of the electron transport chain and ATP synthase, most of the energy
released by oxidizing glucose has been captured to form what? Ans✓✓✓ NADH
Formation of ATP from ADP and Pi requires 7.3 kcal/mole of energy. Which one of
the following reactions could be coupled to ATP synthesis to make ATP synthesis
favorable? Ans✓✓✓ Hydrolysis of phosphoenoylpyruvate. ∆G = - 14.8 kcal/mol
Glucose molecules move into cells lining the intestine against their concentration
gradient driven by the movement of sodium ions (Na+) into the cells down their
concentration gradient. Ans✓✓✓ secondary active transport
Glycolysis is a series of chemical reactions (endergonic and exergonic) by which
the cell can obtain ATP. NAD+ plays a crucial role in the reactions of glycolysis by:
Ans✓✓✓ accepting electrons from glucose, with the result that glucose is
partially oxidized to pyruvate
How do enzymes affect a reaction and why does this happen? Ans✓✓✓ Enzymes
make reactions proceed more quickly because enzymes lower the activation
energy of the reaction.
How do eukaryotic plant and animal cells differ from one another? Ans✓✓✓
Animal cells do not have chloroplasts and cell walls, and plant cells do.
How does an enzyme affect the substrates and products in a cell? Ans✓✓✓ it
increases the chance that two substrates will come together and react
_____ are organisms that derive energy from sunlight. Ans✓✓✓ Phototrophs
A protein that is temporarily associated with a biological membrane is a(n):
Ans✓✓✓ peripheral membrane protein.
Based on the information gained while completing the modeling activity in class,
which of the following changes would most likely result in weight loss? Ans✓✓✓
an increase in the ratio of NAD+/NADH and FADH/FADH2
Carbon atoms that entered glycolysis as glucose will enter the Kerbs cycle as
______ and leave the Krebs cycle as______. Ans✓✓✓ acetyl-CoA; CO2
Cellular respiration is a series of _____ reactions. Ans✓✓✓ catabolic
Cellular respiration releases energy. In cellular respiration: Ans✓✓✓ the chemical
potential energy stored in organic molecules is converted to chemical energy that
can be used to do the work of the cell.
Complete oxidation of glucose to CO2 involves two different mechanisms for
synthesizing ATP: oxidative phosphorylation and substrate-level phosphorylation.
What is TRUE of substrate-level phosphorylation? Ans✓✓✓ An enzyme catalyzes
the transfer of a phosphate group to ADP from an organic molecule to form ATP
Disorders of which organelle are often associated with defects in transport from
compartment to compartment, resulting in poor sorting of protein components
within the cell? Ans✓✓✓ The Golgi Apparatus
,During cellular respiration, what is the fate of the NADH generated by the citric
acid cycle Ans✓✓✓ It is oxidized to NAD+ to power the mitochondrial electron
transport chain.
During glycolysis, a phosphate is transferred from 1,3-bisphosphoglycerate to
ADP. This illustrates what type of process? Ans✓✓✓ substrate-level
phosphorylation
During the citric acid cycle Ans✓✓✓ ATP is synthesized by substrate-level
phosphorylation
During the translation of mRNA molecules, the new polypeptides are often
directed to specific parts of the cell by the presence or absence of short
sequences of amino acids called signal peptides. What would you expect to find in
the polypeptide that will eventually fold to become a transmembrane protein?
Ans✓✓✓ an ER signal peptide and a signal anchor peptide
Electrons enter the electron transport chain at either complex I or II. Electrons
entering through complex I are donated by: Ans✓✓✓ NADH
Energy released by transferring electrons along the electron transport chain is
stored as potential energy in the form of: Ans✓✓✓ a proton gradient
Entropy is often increased by: Ans✓✓✓ Heat
Excess glucose is stored in large branched molecules of: Ans✓✓✓ glycogen in
animals.
, Following oxidation of glucose by glycolysis, the pyruvate dehydrogenase
complex, and the TCA cycle, but prior
to the use of the electron transport chain and ATP synthase, most of the energy
released by oxidizing glucose has been captured to form what? Ans✓✓✓ NADH
Formation of ATP from ADP and Pi requires 7.3 kcal/mole of energy. Which one of
the following reactions could be coupled to ATP synthesis to make ATP synthesis
favorable? Ans✓✓✓ Hydrolysis of phosphoenoylpyruvate. ∆G = - 14.8 kcal/mol
Glucose molecules move into cells lining the intestine against their concentration
gradient driven by the movement of sodium ions (Na+) into the cells down their
concentration gradient. Ans✓✓✓ secondary active transport
Glycolysis is a series of chemical reactions (endergonic and exergonic) by which
the cell can obtain ATP. NAD+ plays a crucial role in the reactions of glycolysis by:
Ans✓✓✓ accepting electrons from glucose, with the result that glucose is
partially oxidized to pyruvate
How do enzymes affect a reaction and why does this happen? Ans✓✓✓ Enzymes
make reactions proceed more quickly because enzymes lower the activation
energy of the reaction.
How do eukaryotic plant and animal cells differ from one another? Ans✓✓✓
Animal cells do not have chloroplasts and cell walls, and plant cells do.
How does an enzyme affect the substrates and products in a cell? Ans✓✓✓ it
increases the chance that two substrates will come together and react
