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49 terms

Chapter 7 Test

STUDY
PLAY
What type of organisms produce the biosphere's food supply?
producers
In a rosebush, chlorophyll is located in...
thylakoids, which are in chloroplasts in the mesophyll cells of a leaf
How does carbon dioxide enter the leaf?
through the stomata
Chlorophyll molecules are in which part of the chloroplast?
grana
You could distinguish a granum from an inner mitochondrial membrane because the granum, but not the inner mitochondrial membrane, would...
have photosynthetic pigments
The source of oxygen produced by photosynthesis has been identified through experiments using radioactive tracers. The oxygen comes from...
water
In photosynthesis, what is the fate of the oxygen atoms present in carbon dioxide? They end up...
in sugar molecules and in water
In an experiment, a plant was given ___ containing radioactive 18O, and the radioactive oxygen atoms were used to make sugar
carbon dioxide
In photosynthesis, plants use carbon from ____ to make sugar and other organic molecules.
carbon dioxide
Cellular respiration and photosynthesis are similar in that they both involve ____.
redox reactions
The photosynthetic event known as the Calvin Cycle occurs in the ____.
stroma
The photo- part of the word photosynthesis refers to ____, whereas -synthesis refers to ____.
the light reactions that occur in the thylakoids ... carbon fixation
the wavelengths of light absorbed by pigment sin the granum are mainly in wich range?
blue-violet and red-orange
The most important role of pigments in photosynthesis is to ____.
capture light energy
What color is most strongly transmitted by chlorophyll?
green
When chloroplast pigments absorb light, ____.
their electrons become excited
the reaction center, antenna molecules, and primary electron acceptors that cluster in the thylakoid membrane form which structure?
photosystem
The synthesis of glucose by photosynthesis is an endergonic process. The source of the energy for the excited electrons is ____.
light
The light reactions of photosynthesis generate high-energy electrons, which end up in ____. The light reaction also produce ____ and ____.
NADPH ... ATP ... oxygen
Where do the electrons needed by photosystem II originate?
water
During photosynthesis in chloroplasts, oxygen is produced from _____ via a series of reactions associated with ____.
water ... photosystem II
What do light reactions not do?
reduce carbon dioxide
During photosynthesis, an electron transport chain is used to ____.
transport electrons from photosystem II to photosystem I
Molecular oxygen is produced during ____.
light reactions of photosynthesis
Light reactions are well located in the thylakoid membrane because ____.
chemiosmosis can be set up across the thylakoid membrane
Both mitochondria and chloroplasts _____.
use a H+ gradient to produce ATP
In addition to its function during electron transport in mitochondria, the chemiosmotic mechanism is important for generating ATP during the _____
light reactions of photosynthesis
During photosynthesis in a eukaryotic cell, a high H+ concentration accumulates or is formed in the ____.
thylokoid compartment
The energy used to produce ATP in the light reactions of photosynthesis comes from ____.
the burning of sugar molecules
The reactions of the Calvin cycle are not directly dependent on light, but they usually do not occur at night. Why?
The Calvin cycle depends on products of the light reactions
The Calvin cycle is a series of reactions that ____.
assemble sugar molecules by fixing carbon
Why is NADP+ needed in photosynthesis?
It forms NADPH to be used in the Calvin cycle
Rubisco is ____.
the enzyme in c3 plants that first captures carbon dioxide to begin the Calvin cycle
What is the role of NADP+ in photosynthesis?
It is reduced and then carries electrons to the Calvin cycle
You have a large, healthy philodendron that you carelessly leave in total darkness while you are on vacay. You are surprised to find that it is still alive when you return. What has the plant been using as a source of energy while in the dark?
Even though the plant received no visible light, it was able to use the short-wave part of the electromagnetic spectrum (gamma rays and X-rays) to carry out photosynthesis
What equation best summarizes photosynthesis?
6 CO2 + 6 H2O —> C6H12O6 + 6 O2
The light reactants of photosynthesis use ____ and produce _____.
water ... NADPH
____ has a longer wavelength than ____.
red ... green
What phosphorylates ADP to make ATP?
Photosystem II
What releases energy that is used to pump hydrogen ions from the stroma into the thylakoid compartment?
ATP synthase
What splits water into 1/2 O2, H+, and e-?
Photosystem I
Energized electrons from ____ enter an electron transport chain are then used to reduce NADP+.
electron transport chain
Carbon fixation involves the addition of carbon dioxide to ___.
RuBP
After 3-PGA is phosphorylated, it is reduces by...
NADPH
How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?
6
In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?
3
In C3 plants the conservation of water promotes...
photorespiration
In C4 and CAM plants carbon dioxide in fixed in the ____ of mesophyll cells.
cytoplasm
C4 plants differ from C3 and CAM plants in that C4 plants ____.
transfer fixed carbon dioxide cells in which the Calvin cycle occurs