Chemical Reactions
Kinetic/Potential Energy
Oxidation-Reduction
Harnessing Energy
Harnessing Energy 2
100
When chemical reactions occur the _______but the _________.
A. atoms retain their identities; the arrangement of bonds changes.
Choice B. identity of atoms changes; the arrangement of bonds is retained
Choice C. number of bonds per atom changes; the total number of bonds are retained
A. atoms retain their identities; the arrangement of bonds changes.
100
Which of the following is an example of kinetic energy?
A. a C-H bond in a sugar molecule
B. water behind a dam
C. a ball at the top of stairs
D. a photon of light
E. gasoline in an auto gas tank
D. A photon of light
100
The reaction of iron with oxygen to form iron oxide is an example of an oxidation-reduction reaction: 4Fe + 3O2 → 2Fe2O3.
In this reaction ______loses electrons and is _________.
A. O2; oxidized
B. Fe; oxidized
C. O2; reduced
D. Fe; reduced
E. Fe2O3; reduced
B. Fe; oxidized
100
Light energy is converted to chemical energy in the:
A. thylakoid
B. cytoplasm
C. central vacuole
D. nucleus
E. mitochondria
a. Thylakoid
100
The primary reducing agent in the Calvin Cycle is:
A. NADPH
B. water
C. NAD+
D. oxygen
E. NADP+
A.NADPH
200
When chemical reactions occur the __________but the ___________.
A. the pairing of atoms that share electron pairs changes; individual atomic nuclei stay the same
B. number of protons and neutrons change; shared electrons stay the same
C. number of shared electron pairs is unchanged; number of atomic nuclei changes
A. the pairing of atoms that share electron pairs changes; individual atomic nuclei stay the same
200
Which of the following is an example of potential energy?
A. chemical transport, as in the sodium-potassium pump
B. contraction of a muscle cell
C. flow of sodium ions through a membrane channel
D. an electrochemical gradient across the cell membrane
D. an electrochemical gradient across the cell membrane
200
The reaction of iron with oxygen to form iron oxide is an example of an oxidation-reduction reaction: 4Fe + 3O2 → 2Fe2O3.
In this reaction ______ gains electrons and is _________.
A. O2; oxidized
B. Fe; oxidized
C. O2; reduced
D. Fe; reduced
E. Fe2O3; reduced
C. O2; reduced
200
Protons in a mitochondrion flow through an ATP synthase from the:
A. cytoplasm to the intermembrane space
B. intermembrane space to the cytoplasm
C. intermembrane space to the matrix
D. matrix to the intermembrane space
C. intermembrane space to the matrix
200
The oxidation of pyruvate occurs in the:
A. mitochondrial matrix
B. cytoplasm
C. mitochondrial intermembrane space
D. stroma
E.lumen of the thylakoid.
A. mitochondrial matrix
300
When CO2 and H2O react to form H2CO3, the number of bonds broken in H2O is____and in CO2 is _____.
A. one; two
B. two; one
C. two; two
D. one; one
D. one; one
300
Table sugar can burn in the following reaction if ignited: C6H12O6 + 6O2 → 6CO2 + 6H2O
In the process, some potential energy of the sugar becomes kinetic energy. Which of the following represents kinetic energy from this reaction?
A. Some of the sugar becomes energy
B. The products and their surroundings have more heat.
C. The products are simpler than the starting molecule.
B. The products and their surroundings have more heat.
300
The reaction of iron with oxygen to form iron oxide is an example of an oxidation-reduction reaction: 4Fe + 3O2 → 2Fe2O3.
In this reaction each iron atom will:
A. gain an oxygen
B. gain 3 electrons
C. lose 3 electrons
D. gain 1.5 electrons
E. lose 1.5 electrons
C. lose 3 electrons
300
The enzyme called rubisco:
A. breaks a 1-carbon molecule off of a 6-carbon molecule
B. connects a 3-carbon molecule to a 5-carbon molecule
C. breaks a 3-carbon molecule into 1-carbon and 2-carbon molecules
D. connects a 1-carbon molecule to a 5-carbon molecule
E. connects two 3-carbon molecules into a 6-carbon molecule
D. connects a 1-carbon molecule to a 5-carbon molecule
300
In aerobic respiration, NADH is oxidized at _______, while FADH2 is oxidized at _______.
A. Complex II; Complex III
B. Photosystem II; Photosystem I
C. Photosystem I; Photosystem II
D. Complex I; Complex I
E. Complex I; Complex II
E. Complex I; Complex II
400
The carbon atom in CO2 shares _______electron pairs. After the reaction with H2O to form H2CO3 is completed, the carbon atom shares ________ electron pairs.
A. two; two
B. four; four
C. two; three
D. three; two
B. four; four
400
Which of the following accounts for the higher potential energy of C–C and C–H bonds compared to C–O, and H–O bonds?
A. The electrons in C–C and C–H are in lower orbitals
B. The atomic nuclei of C–O and H–O are farther apart.
C. The electrons in C–C and C–H are farther from the nuclei.
D. The electrons in C–O and H–O are farther from the nuclei.
C. The electrons in C–C and C–H are farther from the nuclei.
400
Nicotinamide adenine dinucleotide is an electron carrier in many important cellular reactions. It exists in an oxidized form (NAD+) and a reduced form (NADH). Identify the missing component in the following reaction. NAD+ + ____ + H+ → NADH
A. H2O
B. O2
C. 2e-
D. 4e-
E. heat
C. 2e-
400
The terminal electron acceptor of a photosynthetic electron transport chain is:
A. NAD+
B. oxygen
C. NADPH
D. water
E. NADP+
E. NADP+
400
The energy required to drive the synthesis of the majority of the ATP generated during aerobic respiration comes most directly from:
A. the movement of electrons through an electron transport chain
B. removal of a phosphate group from another molecule
C. the flow of protons through an ATP synthase complex
D. the conversion of glucose into two molecules of pyruvate
E. sunlight.
C. the flow of protons through an ATP synthase complex
500
When H2CO3 reacts to form CO2 and H2O, what is the net change in the number of shared electron pairs?
A. plus two
B. minus two
C. minus three
D. zero
D. Zero
500
Many cellular processes represent work that requires the expenditure of energy. Which of the following is not a cellular process that requires the cell to expend energy?
A. diffusion of water into cells
B. contraction of muscle cells
C. synthesis of large biomolecules like proteins and nucleic acids
D. keeping sodium ion concentration lower inside a cell than outside the cell
A. diffusion of water into cells
500
Question 5 of 5
The reactions shown here present the overall oxidation-reduction reaction in which elemental iron and molecular oxygen react to form iron oxide (a), and also the half-reactions showing the oxidation part and the reduction part (b and c). Compare this reaction and its half-reactions to the reaction of nicotinamide adenine dinucleotide as an electron carrier in many important cellular reactions. NAD+ + 2e– + H+ → NADH. Which reaction or half-reaction above is most similar to this NAD+/NADH reaction?
A. reaction a
B. reaction b
C. reaction c
D. It combines both reaction b and reaction c.
C. reaction c
500
The terminal electron acceptor of a mitochondrial electron transport chain is:
A. NADP+
B. NAD+
C. NADPH
D. oxygen
E. water
D. oxygen
500
The first stage in the production of ATP via the oxidation of glucose molecules is referred to as:
A. the electron transport chain
B. glycolysis
C. photosynthesis
D. the citric acid cycle
E. the Calvin cycle.
B. glycolysis