82 ❯ STEP 4. Review the Knowledge You Need to Score High
To sum up these two variations of photosynthesis:
C 4 photosynthesis:photosynthetic process that first converts CO 2 into a 4-carbon molecule
in the mesophyll cells, converts that product to malate, and then shuttles the malate into
the bundle sheath cells. There, malate releases CO 2 , which reacts with rubisco to produce
the carbohydrate product of photosynthesis.
CAM photosynthesis:plants close their stomata during the day, collect CO 2 at night, and
store the CO 2 in the form of acids until it is needed during the day for photosynthesis.Review Questions
Questions 1–4 refer to the following answer choices—
use each answer only once.
A. Transpiration
B. Calvin cycle
C. CAM photosynthesis
D. Cyclic photophosphorylation
E. Noncyclic photophosphorylation- Plants use this process so that they can open their
stomata at night and close their stomata during
the day to avoid water loss during the hot days,
without depleting the plant’s CO 2 reserves. - Uses NADPH, ATP, and CO 2 as the inputs to
its reactions. - Photosynthetic process that has ATP as its sole
product. There is no oxygen and no NADPH
produced from these reactions. - The process by which plants lose water via
evaporation through their leaves. - The photosynthetic process performed by some
plants in an effort to survive the hot and dry con-
ditions of climates such as the desert is called
A. carbon fixation.
B. C 3 photosynthesis.
C. C 4 photosynthesis.
D. cyclic photophosphorylation.
E. noncyclic photophosphorylation. - Which of the following is the photosynthetic
stage that produces oxygen?
A. The light-dependent reactions
B. Chemiosmosis
C. The Calvin cycle
D. Carbon fixation
E. Photorespiration
7. Which of the following reactions occur in both
cellular respiration and photosynthesis?
A. Carbon fixation
B. Fermentation
C. Reduction of NADP+
D. Chemiosmosis
E. Formation of NADH
8. Which of the following is nota product of the
light-dependent reactions of photosynthesis?
A. O 2
B. ATP
C. NADPH
D. Sugar
9. Which of the following is an advantage held by
a C 4 plant?
A. More efficient light absorption
B. More efficient photolysis
C. More efficient carbon fixation
D. More efficient uptake of carbon dioxide into
the stomata
E. More efficient ATP synthesis during
chemiosmosis
10.Carbon dioxide enters the plant through the
A. Stomata
B. Stroma
C. Thylakoid membrane
D. Bundle sheath cell
11.Which of the following is the source of the
oxygen released during photosynthesis?
A. CO 2
B. H 2 O
C. Rubisco
D. PEP carboxylase
E. Pyruvate
KEY IDEA