sunlight
The ultimate energy source that supports most life on Earth is _____.
They use light energy to drive the synthesis of organic molecules.
Plants are photosynthetic autotrophs. What does this mean?
chloroplasts
The photosynthetic membranes are found in the _____ in plant cells.
glucose … oxygen
The end products of photosynthesis are _____ and _____.
It is an oxygen source as well as a source of stored energy.
Which of the following includes some of the benefits of photosynthesis?
NADPH
Which of the following is produced by the light reactions of photosynthesis and consumed by the Calvin cycle?
UV radiation and infrared radiation
In the electromagnetic spectrum, the type of radiation that we call visible light occurs between __________.
blue-violet … red-orange
As a consequence of the work of the biologist, Theodor Engelmann, others showed that chloroplasts absorb light mainly in the _____ and _____ part of the spectrum.
chlorophyll a
Which of the following is a pigment that participates directly in the light reactions by absorbing mainly blue-violet and red light?
splitting water
When light strikes chlorophyll molecules, they lose electrons, which are ultimately replaced by other electrons obtained by __________.
making sugar
The overall function of the Calvin cycle is __________.
NADPH
Which of the following provides a source of energy for the Calvin Cycle?
carbon dioxide is used in the Calvin cycle to make sugar
Forests are considered carbon storage sinks because __________.
Vigorously growing plants remove a lot of carbon dioxide from the air.
Which of the following is a good reason for using fast-growing trees as fuel?
Large, broad leaves
Which of the following leaf types would be the most efficient at absorbing sunlight?
Stomata
Which of the following structures allows for gas exchange between the tissues of a leaf and the atmosphere?
True
True or false. Guard cells open during the day to allow gases to flow through the stomata.
6 CO2 + 6 H2O → C6H12O6 + 6 O2
Which of these equations best summarizes photosynthesis?
water … NADPH
The light reactions of photosynthesis use _____ and produce _____.
Red … green
_____ has a longer wavelength than _____.
autotrophs
Which of these types of organisms produce the biosphere’s food supply?
thylakoids, which are in chloroplasts in the mesophyll cells of a leaf
In a rosebush, chlorophyll is located in _____.
through the stomata
How does carbon dioxide enter the leaf?
grana
Chlorophyll molecules are in which part of the chloroplast?
have photosynthetic pigments
You could distinguish a granum from a mitochondrial membrane because the granum, but not the mitochondrial membrane, would __________.
redox reactions
Cellular respiration and photosynthesis are similar in that both involve __________.
stroma
The photosynthetic event known as the Calvin cycle occurs in the _____.
the light reactions that occur in the thylakoids … the incorporation of carbon dioxide
The “photo-” part of the word “photosynthesis” refers to __________, whereas “-synthesis” refers to __________.
blue-violet and red-orange
The wavelengths of light absorbed by pigments in the granum are mainly in which range?
green
Which one of the following colors is most strongly reflected by chlorophyll?
green
Which of these wavelengths is least useful for photosynthesis?
capture light energy
The most important role of pigments in photosynthesis is to __________.
their electrons become excited
When chloroplast pigments absorb light, __________.
light
The synthesis of glucose by photosynthesis requires energy. The source of the energy for the excited electrons is _____.
water
The source of the oxygen produced by photosynthesis has been identified through experiments using radioactive tracers. The oxygen comes from _____.
NADPH … ATP … oxygen
The light reactions of photosynthesis generate high-energy electrons, which end up in _____. The light reactions also produce _____ and _____.
water
Where do the electrons needed by the water-splitting photosystem originate?
remove electrons from H2O
Which of the following occurs during the light reactions?
NADPH … NADH
The _____ of photosynthesis performs a task similar to that of the _____ of cellular respiration.
use an H+ gradient to produce ATP
Both mitochondria and chloroplasts __________.
movement of H+ through a membrane
The energy used to produce ATP in the light reactions of photosynthesis comes from __________.
It forms NADPH to be used in the Calvin cycle.
Why is NADP+ needed in photosynthesis?
in sugar molecules and in water
In photosynthesis, what is the fate of the oxygen atoms present in CO2? They end up __________.
carbon dioxide
In photosynthesis, plants use carbon from _____ to make sugar and other organic molecules.
assemble sugar molecules by incorporating carbon
The Calvin cycle is a series of reactions that __________.
The Calvin cycle depends on products of the light reactions.
The reactions of the Calvin cycle are not directly dependent on light, but they usually do not occur at night. Why?
