The light-independent reactions are sometimes called the Calvin cycle because of the cyclical nature of the process. Although the light-independent reactions do not use light as a reactant (and as a result can take place at day or night), they require the products of the light-dependent reactions to function.
Why is light needed for light-dependent reactions?
The light-dependent reactions use light energy to make two molecules needed for the next stage of photosynthesis: the energy storage molecule ATP and the reduced electron carrier NADPH.
What is required for light-independent reactions to occur?
The requirements or ingredients for light-independent reactions are carbon dioxide and energy in the form of ATP and NADPH.
How does lack of light affect the light-dependent reaction?
The light dependent reactions of photosynthesis produce energy in the form of ATP, and the electron carrier molecule NADPH, which are needed for the light independent reactions. If the light dependent reactions are stopped, there will be no ATP and NADPH for the light independent reactions, and the plant will die.
Do light-independent reactions only occur in the dark?
In fact, the light independent reactions occur at the same time as the light dependent reactions, because they are driven by the ATP made by the light-dependent reactions. Both systems shut down in the dark. The light-independent reactions can last a little longer if there is ATP remaining in the chloroplast.
Can light independent stage occur without 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.
What is required for both the light dependent and light-independent reactions to proceed?
Light dependent reactions occur in Grana of Chloroplasts, Light Independent reactions occur in Stroma of Chloroplasts. Hence Chloroplasts are required for both the light-dependent and light-independent reactions to proceed. Elaine C. The answer is energy.
Do light-independent reactions only occur at night?
Although the light-independent reactions do not use light as a reactant (and as a result can take place at day or night), they require the products of the light-dependent reactions to function.
What is the difference between light-dependent and light-independent reactions?
In the light-dependent reactions, energy from sunlight is absorbed by chlorophyll and that energy is converted into stored chemical energy. In the light-independent reactions, the chemical energy harvested during the light-dependent reactions drives the assembly of sugar molecules from carbon dioxide.
Where do light-independent reactions occur?
The light-independent reactions represent the known Calvin–Benson–Bassham (CBB) cycle which takes place in the stroma of chloroplasts and is the primary pathway of carbon fixation of C3 plants [119]. The CBB cycle proceeds in three main stages: carboxylation, reduction and regeneration.
What is required for both the light-dependent and light-independent reactions to proceed quizlet?
The L-D reactions require light energy and water, and the L-IND reactions require ATP, NADPH and CO2.
Why do light-independent reactions not occur at night?
– Calvin cycle require ATP & NADPH for production of glucose. – These ATP & NADPH are formed by light reactions. – So dark reactions must occur alongside light reactions. – Therefore, though dark reactions are light independent, they can’t occur at night.
Can light-dependent reactions occur in the dark?
No. As the title says, light-dependent reactions are dependent on light to occur. The light-dependent reaction has two systems, Photosystem 1 and Photosystem 2. The purpose of these structures is to absorb light in turn exciting the electrons that make them up.
Can light reaction happen at night?
Light dependent reactions(taking place in thylakoid discs)of photosynthesis can’t take place in absence of light.
Does dark reaction occur at night?
Does the dark reaction occur at night? No, the dark reaction does not occur at night. It occurs during the day, but the reaction does not use the light directly. Therefore, it is known as the dark reaction.
Which comes first light independent or light-dependent?
The light-dependent reactions convert light energy into chemical energy. The goal of the light-dependent reactions of photosynthesis is to collect energy from the sun and break down water molecules to produce ATP and NADPH. These two energy-storing molecules are then used in the light-independent reactions.
Why is there a need to go on with light-independent reactions Why not stop with the light-dependent reactions since ATP and NADPH are energy carrying molecules?
Why is there a need to go on with Light-Independent reactions? Why not stop with Light-Dependent Reactions since ATP and NADPH are energy carrying molecules? The Light-Independent uses ATP and NADPH from the Light-Dependent reactions to produce high energy carbohydrates and oxygen. Where does Carbon Dioxide come from?
What are the four reactants needed for light reaction to occur?
In photosynthesis, water, carbon dioxide, ATP, and NADPH are reactants. RuBP and oxygen are products. In photosynthesis, water and carbon dioxide are reactants. GA3P and oxygen are products.
Where does the light-independent reactions get their energy from quizlet?
The light-dependent reactions require light and water, occur in the thylakoids, and produce ATP and NADPH. The light-independent reactions require carbon dioxide, occur in the stroma, and produce high-energy sugars.
Why should the light-dependent reaction occur before the light-independent reaction?
Light-dependent reactions occur before light-independent reactions because of the following reactions: Light-dependent reactions take place in thylakoid membranes (grana) of chloroplasts in presence of light. , which then passes into the stroma of the chloroplast.
Why are light-independent reactions called?
These reactions are also called the light-independent reactions because they are not directly driven by light. In the Calvin cycle, carbon atoms from CO2start text, C, O, end text, start subscript, 2, end subscript are fixed (incorporated into organic molecules) and used to build three-carbon sugars.
Which of the following is not required during the light-dependent reaction for photosynthesis to occur?
Which of the following is not required for the light-independent reactions of photosynthesis? ATP, stroma, NADPH, and CO2 are required for the light-independent reactions of photosynthesis. H2O is not required for the Calvin cycle.
Do dark reactions require light?
Dark reaction of photosynthesis does not require light. Both the light and dark reactions occur in the day. As dark reaction does not require light it doesn’t meant it occurs at night it only requires products of light reaction like ATP and NADPH.
Can photosynthesis take place without sunlight?
At night, or in the absence of light, photosynthesis in plants stops, and respiration is the dominant process. The plant uses energy from the glucose it produced for growth and other metabolic processes.
Do not need light energy to power their reactions and can occur day or night?
Dark reactions or “light independent reactions” do not need light energy to power their reactions and can occur day or night. Discovered by three scientists, the dark reactions are also called the Calvin-Bensen-Bassham cycle or just Calvin Cycle.
What is difference between light and dark reaction?
The main difference between light and dark reaction is that light reaction is the first stage of photosynthesis, which traps light energy in order to produce ATP and NADPH whereas dark reaction is the second stage of photosynthesis, which produces glucose by using the energy form ATP and NADPH produced from the light …
What provides electrons for the light reactions?
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 are the reactants and products of light-dependent and light-independent reactions?
The products of light-dependent pathways of photosynthesis are Oxygen, ATP, and NADPH. The reactants of light-independent reactions are ATP, NADPH, and Carbon Dioxide. The main purpose of the light independent reaction is to produce glucose.
Why is the light dependent stage required to occur before the light independent stage?
Why should the light dependent reaction occurs before the light independent reaction? In light – dependent photosynthesis, the photosynthetic pigment absorbs the light energy and convert it into chemical energy, ATP and NADPH2 . … So the light-dependent reaction should occur before the light-independent reaction.
Why does light reactions precede dark reaction during photosynthesis?
Why does light reactions precede dark reaction during photosynthesis? Light provides energy for the synthesis of glucose from carbon dioxide and water during photosynthesis. … Thus light reaction must precede dark reaction.
What is the byproduct of light independent reaction?
The light-independent reactions can proceed once products (NADPH and ATP) of the light-dependent reactions are present in the chloroplast.
What are the products of light independent reaction used to power the light independent reaction?
NADPH and ATP are the products of light-dependent reactions used to power the light-independent reaction.
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.
Which of the following is not required by light-independent reactions?
Calvin cycle is a dark reaction which means it is a light-independent cycle. It occurs in the absence of light during night time. It also occurs during daytime but the energy from sunlight is not needed by it to perform its function.
Does light-independent reaction produce ATP?
Photosystems absorb light and use electron transport chains to convert energy into the chemical energy of ATP and NADPH. The subsequent light-independent reactions then assemble carbohydrate molecules with this energy.
In what way are the light-dependent and light?
The light-independent reactions release energy, and the light-dependent reactions require energy. The light-dependent reactions pass electrons through an electron transport chain to the light-independent reactions.
What is the difference between light-dependent and light-independent reactions quizlet?
The light-dependent reac-tions require light and water, occur in the thylakoids, and produce ATP and NADPH. The light-independent reactions require carbon dioxide, occur in the stroma, and produce high-energy sugars.