AP Biology Photosynthesis BIZ Review KEY
1)
When oxygen is released as a result of
photosynthesis, it is a by-product of which of the
following?
A) reducing NADP+
B) splitting the water molecules
C) chemiosmosis
D) the electron transfer system of photosystem I
E) the electron transfer system of photosystem II
2) Assume a thylakoid is somehow punctured so that
the interior of the thylakoid is no longer separated
from the stroma. This damage will have the most
direct effect on which of the following processes?
A) the splitting of water
B) the absorption of light energy by chlorophyll
C) the flow of electrons from photosystem II to
photosystem I
D) the synthesis of ATP
E) the reduction of NADP+
3) In a plant cell, where are the ATP synthase
complexes located?
A) thylakoid membrane
B) plasma membrane
C) inner mitochondrial membrane
D) A and C
E) A, B, and C
4) Which of the following statements best represents
the relationships between the light reactions and the
Calvin cycle?
A) The light reactions provide ATP and NADPH to
the Calvin cycle, and the cycle returns ADP, Pi,
and NADP+ to the light reactions.
B) The light reactions provide ATP and NADPH to
the carbon fixation step of the Calvin cycle, and
the cycle provides water and electrons to the
light reactions.
C) The light reactions supply the Calvin cycle with
CO2 to produce sugars, and the Calvin cycle
supplies the light reactions with sugars to
produce ATP.
D) The light reactions provide the Calvin cycle with
oxygen for electron flow, and the Calvin cycle
provides the light reactions with water to split.
E) There is no relationship between the light
reactions and the Calvin cycle.
For question 5-6, compare the light reactions with the Calvin
cycle of photosynthesis in plants.
5) Produces NADPH
A) light reactions alone
B) the Calvin cycle alone
C) both the light reactions and the Calvin cycle
D) neither the light reactions nor the Calvin cycle
E) occurs in the chloroplast but is not part of
photosynthesis
6) Requires CO2
A) light reactions alone
B) the Calvin cycle alone
C) both the light reactions and the Calvin cycle
D) neither the light reactions nor the Calvin cycle
E) occurs in the chloroplast but is not part of
photosynthesis
7) The chemical reaction for photosynthesis is
6 CO2 + 12 H2O + light energy → C6H12O6 + 6 O2 + 6 H2O
If the input water is labeled with a radioactive isotope of
oxygen, 18O, then the oxygen gas released as the
reaction proceeds is also labeled with 18O. Which of the
following is the most likely explanation?
A) During the light reactions of photosynthesis, water is
split, the hydrogen atoms combine with the CO2, and
oxygen gas is released.
B) During the light reactions of photosynthesis, water
is split, removing electrons and protons, and oxygen
gas is released.
C) During the Calvin cycle, water is split, regenerating
NADPH from NADP+ and oxygen gas is released.
D) During the Calvin cycle, water is split, the hydrogen
atoms are added to intermediates of sugar synthesis,
and oxygen gas is released.
DEFINE THEIR ROLES IN THE PRODUCTION OF
PHOTOSYNTHESIS!!!
ATP – made in light-dependent reaction and used in Calvin
Cycle to make glucose
NADPH – Carries electrons from thylakoid to stroma (to be
used in the Calvin Cycle)
ATP Synthase – uses H+ gradient to bond ADP+P to make ATP
H+ - sourced from water and pumped into the thylakoid
membrane. Concentration gradient used to fuel ATP synthase
Photosystem I – uses light to re-energize electrons that will
later be picked up by NADP+ to form NADPH
Photosystem II – uses light energy to split H2O molecule.
Oxygen is removed as waste, hydrogen is pumped into
thylakoid
Electron Transport Chain – uses electron energy to pump H+
molecules into the thylakoid
Plant Pigments – absorb light energy to be used in
photosynthesis (found in photosystems II and I)
CO2 – used in calvin cycle to produce glucose
Light – absorbed by pigments and used to excite electrons
and split water
O2 - WASTE!!!!!!!!!!!!!!!!!!
Glucose – final product of photosynthesis. Can be broken
down in respiration to make ATP.
PGAL/G3P – produced in the calvin cycle. Two of these make a
glucose molecule.
RuBP – bonded to CO2 by RuBisCo in the Calvin cycle (1st step)
RuBisCo – enzyme used in Calvin cycle to “fix” CO2
Thylakoid Membrane – location of light-dependent reaction
Thylakoid Lumen –fills with H+ ions during the light reaction
(the inside space of the thylakoid)
AP Biology Photosynthesis BIZ Review KEY