BS 161 Exam 3 ACTUAL Questions and
CORRECT Answers
Which of the following sequences CORRECTLY represents the flow of energy through living
systems? - CORRECT ANSWER - light → photosynthesis → carbohydrate → cellular
respiration → ATP → heat
Where is the photosynthetic electron transport chain located in plant cells? - CORRECT
ANSWER - in the thylakoid membranes of the chloroplast
In a thylakoid membrane, absorbed light energy is passed from one chlorophyll molecule to
another until it is: - CORRECT ANSWER - passed to a reaction center.
During photosynthesis, _____ is reduced to _____. - CORRECT ANSWER - carbon
dioxide; sugar
Which of the following CORRECTLY lists the three steps of the Calvin cycle? - CORRECT
ANSWER - carboxylation, reduction, and regeneration
Which of the following CORRECTLY describes the role of rubisco in the Calvin cycle? -
CORRECT ANSWER - Rubisco incorporates CO2 from the atmosphere into an organic
molecule.
How many CO2 molecules must enter the Calvin cycle for each molecule of triose phosphate
that can be exported from the chloroplast? - CORRECT ANSWER -3
In the Calvin cycle, NADPH is: - CORRECT ANSWER - oxidized.
Which step of the Calvin cycle would be affected first by a lack of NADPH? - CORRECT
ANSWER - reduction
, Which of the following are products of the light-dependent reactions of photosynthesis that are
required by reactions in the Calvin cycle? - CORRECT ANSWER - ATP and NADPH
Which of the following are produced directly as a result of the movement of electrons through
the photosynthetic electron transport chain? - CORRECT ANSWER - ATP and NADPH
During photosynthesis in plants and algae, _____ is being oxidized and _____ is being reduced. -
CORRECT ANSWER - H2O; CO2
In plants and algae, _____ is the source of the electrons needed for photosynthesis. - CORRECT
ANSWER - H2O
In plants and algae, which of the following is a by-product of photosynthesis? - CORRECT
ANSWER - O2
Which one of the following is NOT a product when photosystem II oxidizes a molecule of
water? - CORRECT ANSWER - carbon dioxide
Which of the following CORRECTLY lists the path taken by electrons through the light
dependent reactions of photosynthesis? - CORRECT ANSWER - water → photosystem II
→ cytochrome b6f → photosystem I → NADPH
Why is the photosynthetic electron transport chain sometimes referred to as the "Z scheme"? -
CORRECT ANSWER - Because the energy level of the electrons increases and decreases
and increases and decreases.
As electrons flow through the light-dependent reactions, they become associated with several
molecules and molecular complexes. When do the electrons have the GREATEST amount of
energy? - CORRECT ANSWER - when they are associated with photosystem I
CORRECT Answers
Which of the following sequences CORRECTLY represents the flow of energy through living
systems? - CORRECT ANSWER - light → photosynthesis → carbohydrate → cellular
respiration → ATP → heat
Where is the photosynthetic electron transport chain located in plant cells? - CORRECT
ANSWER - in the thylakoid membranes of the chloroplast
In a thylakoid membrane, absorbed light energy is passed from one chlorophyll molecule to
another until it is: - CORRECT ANSWER - passed to a reaction center.
During photosynthesis, _____ is reduced to _____. - CORRECT ANSWER - carbon
dioxide; sugar
Which of the following CORRECTLY lists the three steps of the Calvin cycle? - CORRECT
ANSWER - carboxylation, reduction, and regeneration
Which of the following CORRECTLY describes the role of rubisco in the Calvin cycle? -
CORRECT ANSWER - Rubisco incorporates CO2 from the atmosphere into an organic
molecule.
How many CO2 molecules must enter the Calvin cycle for each molecule of triose phosphate
that can be exported from the chloroplast? - CORRECT ANSWER -3
In the Calvin cycle, NADPH is: - CORRECT ANSWER - oxidized.
Which step of the Calvin cycle would be affected first by a lack of NADPH? - CORRECT
ANSWER - reduction
, Which of the following are products of the light-dependent reactions of photosynthesis that are
required by reactions in the Calvin cycle? - CORRECT ANSWER - ATP and NADPH
Which of the following are produced directly as a result of the movement of electrons through
the photosynthetic electron transport chain? - CORRECT ANSWER - ATP and NADPH
During photosynthesis in plants and algae, _____ is being oxidized and _____ is being reduced. -
CORRECT ANSWER - H2O; CO2
In plants and algae, _____ is the source of the electrons needed for photosynthesis. - CORRECT
ANSWER - H2O
In plants and algae, which of the following is a by-product of photosynthesis? - CORRECT
ANSWER - O2
Which one of the following is NOT a product when photosystem II oxidizes a molecule of
water? - CORRECT ANSWER - carbon dioxide
Which of the following CORRECTLY lists the path taken by electrons through the light
dependent reactions of photosynthesis? - CORRECT ANSWER - water → photosystem II
→ cytochrome b6f → photosystem I → NADPH
Why is the photosynthetic electron transport chain sometimes referred to as the "Z scheme"? -
CORRECT ANSWER - Because the energy level of the electrons increases and decreases
and increases and decreases.
As electrons flow through the light-dependent reactions, they become associated with several
molecules and molecular complexes. When do the electrons have the GREATEST amount of
energy? - CORRECT ANSWER - when they are associated with photosystem I
