Light reactions harness energy from the sun to produce chemical bonds, ATP, and NADPH. These energy-carrying molecules are made in the stroma where carbon fixation takes place. The light-independent reactions of the Calvin cycle can be organized into three basic stages: fixation, reduction, and regeneration .
What are the steps in light reaction of photosynthesis?
These reactions occur within specialised membrane discs within the chloroplast called thylakoids and involve three steps: Excitation of photosystems by light energy . Production of ATP via an electron transport chain . Reduction of NADP + and the photolysis of water .
What are the 7 steps of light dependent reactions?
- (1st Time) Energy is absorbed from the sun.
- Water is broken down.
- Hydrogen ions are transported across the thylakoid membrane.
- (2nd Time) Energy is absorbed from the sun.
- NADPH is produced from NADP+.
- Hydrogen ions diffuse through the protein channel.
- ADP becomes ATP.
What is the process of light reaction?
“Light reaction is the process of photosynthesis that converts energy from the sun into chemical energy in the form of NADPH and ATP.”
What are the steps of light reactions in order?
- Light absorption in PSII. When light is absorbed by one of the many pigments in photosystem II, energy is passed inward from pigment to pigment until it reaches the reaction center. ...
- ATP synthesis. ...
- Light absorption in PSI. ...
- NADPH formation.
What is the first step in the light-dependent reactions?
The overall function of light-dependent reactions, the first stage of photosynthesis, is to convert solar energy into chemical energy in the form of NADPH and ATP , which are used in light-independent reactions and fuel the assembly of sugar molecules.
What is the order of photosynthesis reaction?
It is convenient to divide the photosynthetic process in plants into four stages, each occurring in a defined area of the chloroplast: (1) absorption of light, (2) electron transport leading to the reduction of NADP + to NADPH , (3) generation of ATP, and (4) conversion of CO 2 into carbohydrates (carbon fixation).
What is light reaction explain with diagram?
Definition. The series of biochemical reactions in photosynthesis that require light energy that is captured by light-absorbing pigments (such as chlorophyll) to be converted into chemical energy in the form of ATP and NADPH. Supplement.
What are the three steps of light reactions?
The light-independent reactions of the Calvin cycle can be organized into three basic stages: fixation, reduction, and regeneration .
What goes in light dependent reaction?
The light-dependent reaction is a photochemical reaction taking place in the thylakoid membranes of chloroplasts, where light energy is transformed into adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH) .
Do light-dependent reactions produce oxygen?
In the light-dependent reactions, which take place at the thylakoid membrane, chlorophyll absorbs energy from sunlight and then converts it into chemical energy with the use of water. ... The light-dependent reactions release oxygen as a byproduct as water is broken apart .
What are the 3 products of the light-dependent reactions?
The exergonic light-dependent reactions of photosynthesis convert light energy into chemical energy, producing ATP and NADPH . These reactions occur in the thylakoids of the chloroplasts. The products of the light-dependent reactions, ATP and NADPH, are both required for the endergonic light-independent reactions.
Is the Calvin cycle light-dependent?
Overview of the Calvin cycle
This process is fueled by, and dependent on, ATP and NADPH from the light reactions . Unlike the light reactions, which take place in the thylakoid membrane, the reactions of the Calvin cycle take place in the stroma (the inner space of chloroplasts).
What are the major events of light reaction?
The important events of light reaction are (i) Excitation of chlorophyll molecule to emit a pair of electrons and use of their energy in the formation of ATP from ADP + Pi . This process is called photophosphorylation. Splitting of water molecule (a) (b) End products of light reaction are NADPH and ATP.
What is the other name for light reaction?
The other name of light reaction is photo reaction .
What is the 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 ...
