The light-dependent reactions
release oxygen as a byproduct
as water is broken apart. In the Calvin cycle, which takes place in the stroma, the chemical energy derived from the light-dependent reactions drives both the capture of carbon in carbon dioxide molecules and the subsequent assembly of sugar molecules.
Does the Calvin cycle split water and release oxygen?
The Calvin Cycle converts three water and three carbon dioxide molecules into one molecule of glyceraldehyde.
The six left over oxygen atoms are released into the atmosphere
where they are available for use in respiration.
What is required for the Calvin cycle?
The Calvin Cycle
All three necessary conditions are required –
chlorophyll pigments, the chloroplast “theater,” and enzyme catalysts
. The first stage transforms light energy into chemical energy, stored to this point in molecules of ATP and NADPH.
What happens to CO2 in the Calvin cycle?
In the Calvin cycle,
carbon dioxide molecules (CO2) are combined with each other and with the electrons and Hydrogen ions from NADPH to form glucose
(C6H12O6).
Is CO2 reduced in the Calvin cycle?
In the Calvin cycle, the ATP made in the light reaction provides the energy and the NADPH provides the reducing power needed to make sugar from carbon dioxide and water.
Carbon dioxide is reduced into G3P
.
Why is there a need to split water in the light-dependent reaction it is to provide?
During Light reactions of Photosynthesis, the chlorophyll will be activated by light. This light activated chlorophyll will split the water molecule. This process is called Photolysis. Water molecule is split
to release H+ ions and also oxygen
.
Why is water split during the Light reactions?
What is the purpose of the splitting of water in the light-dependent reaction?
To replace the electron in the chlorophyll
, a molecule of water is split. This splitting releases two electrons and results in the formation of oxygen (O
2
) and 2 hydrogen ions (H
+
) in the thylakoid space.
When water is split what is released?
Water splitting is the chemical reaction in which water is broken down into
oxygen and hydrogen
: 2 H
2
O → 2 H
2
+ O. Efficient and economical water splitting would be a technological breakthrough that could underpin a hydrogen economy, based on green hydrogen.
What would happen if the Calvin cycle stopped working?
Even organisms that eat other organisms, such as carnivores, depend on the Calvin cycle. Without it,
they wouldn't have the food, energy, and nutrients they need to survive
. The Calvin cycle has four main steps: carbon fixation, reduction phase, carbohydrate formation, and regeneration phase.
Does the Calvin cycle require light?
The Calvin cycle refers to the light-independent reactions in photosynthesis that take place in three key steps. Although the Calvin Cycle is not directly dependent on light,
it is indirectly dependent on light
since the necessary energy carriers (ATP and NADPH) are products of light-dependent reactions.
Does water produce glucose?
Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose.
Does the Calvin cycle release oxygen?
Plants rely on the photosynthesis process to obtain energy by two steps: (1) to convert carbon dioxide and water into glucose from sunlight in thylakoids; (2)
in the Calvin cycle, energy (adenosine triphosphate, ATP) and oxygen (O
2
) are released when decomposing glucose into pyruvate in stroma
[14].
Which of the following is not directly used in the Calvin cycle?
Which of the following is NOT directly used in the Calvin Cycle? While
water
is used in the light reactions of photosynthesis, it is not used in the Calvin cycle. In the Calvin cycle ATP helps to fuel the fixation of carbon from carbon dioxide into glucose, and this reaction is catalyzed by the enzyme rubisco.
Does the Calvin cycle require oxygen?
The oxygen in the glucose molecule comes from the carbon dioxide, which is used in the Calvin Cycle
. As you mentioned, the oxygen in water is broken down in the non-cyclic phosphorylation process to obtain an electron which can be used in the photosystem I and II to form ATP and NADPH.
How does Calvin cycle convert CO2 to glucose?
The reactions of the Calvin cycle add carbon (from carbon dioxide in the atmosphere) to a simple five-carbon molecule called RuBP. These reactions
use chemical energy from NADPH and ATP that were produced in the light reactions
. The final product of the Calvin cycle is glucose.
What happens to glucose after the Calvin cycle?
Each turn of the Calvin cycle “fixes” one molecule of carbon that can be used to make sugar. It takes three turns of the Calvin cycle to create one molecule of glyceraldehyde-3 phosphate. After six turns of the Calvin cycle,
two molecules of glyceraldehyde-3 phosphate can be combined to make a glucose molecule
.
Which part of the Calvin cycle would be affected if a cell could not produce the enzyme RuBisCO?
Which part of the Calvin cycle would be affected if a cell could not produce the enzyme RuBisCO?
None of the cycle could take place
, because RuBisCO is essential in fixing carbon dioxide. Specifically, RuBisCO catalyzes the reaction between carbon dioxide and RuBP at the start of the cycle.
What gets reduced in the Calvin cycle?
In the carbon fixation phase of the Calvin cycle, inorganic carbon in the form of carbon dioxide becomes incorporated into organic form. Essentially,
carbon dioxide
is reduced to provide a higher energy molecule.
What is reduced in the Calvin cycle?
In the second stage, six ATP and six NADPH are used to convert the six 3-PGA molecules into
six molecules of a three-carbon sugar (G3P)
. This reaction is considered a reduction because NADPH must donate its electrons to a three-carbon intermediate to make G3P.
Do light reactions require CO2?
Explanation: The light dependent reaction of photosynthesis requires energy in the form of light so as to convert CO2 and H2O into glucose and other substrates. The
light independent reaction does not require light
but can also occur in the presence of light.
What happens to water in light-dependent reactions?
In photosynthesis, a light-dependent reaction uses light energy from the sun to split water which has been taken in by the organism. Water, when split,
gives oxygen, hydrogen, and electrons
.
Can light reactions function without water?
Light reactions occur when plants synthesize food from carbon dioxide and water, referring specifically to the part of energy production that
requires light and water to generate electrons needed for further synthesis
. Water provides the electrons by splitting into hydrogen and oxygen atoms.
What happens to water in the light reactions?
The water is split during the light reaction to form oxygen gas and hydrogen ions
. The hydrogen ions are used by the chloroplast to produce ATP.
What is the name of the process that splits water?
Splitting water into its two components is much easier to do and is called
water electrolysis
. Making hydrogen or oxygen this way seems simple. But as you probably suspected, this reverse reaction needs an energy input, which is why it is also called an endothermic reaction.
Why is water split during the light dependent reactions quizlet?
The oxygen released during photosynthesis
comes from the splitting of water during the light-dependent reaction. 3. Remember, the electrons lost from the reaction center in photosystem II must be replaced. The splitting of water serves to replace these lost electrons.
In which component of the light reaction is water broken down?
Water is split on the
thylakoid lumen side of the thylakoid membrane
, so the protons are released inside the thylakoid, contributing to the formation of a gradient. The high-energy electron travels down an electron transport chain in , losing energy as it goes.
