- 1 What links photosystem 2 to photosystem 1 in the light reactions?
- 2 How are the two photosystems linked?
- 3 How are photosystem 1 and 2 connected?
- 4 What connects the light reaction with the Calvin cycle?
- 5 What are the 7 steps of light dependent reactions?
- 6 On which side of the membrane do H+ ions build up?
- 7 How are photosystem I and II similar and different?
- 8 What two main products result from photosynthesis?
- 9 What are the two roles of water in the light dependent reaction?
- 10 What is the difference between ps1 and ps2?
- 11 What is the purpose of photosystem 2?
- 12 What happens in photosystem II?
- 13 Why is the Calvin cycle important to most ecosystems?
- 14 How do the light reactions produce ATP?
- 15 What is CO2 fixation?
Because the continuous passing of electrons along the electron transport chain powers the production of ATP, ATP production would stop. Additionally, because the electron transport chain links photosystem II to photosystem I, any interruption in the transport chain would also halt NADPH production.
Each photosystem consists of two closely linked components: the first is the antenna complex formed by hundreds of pigment molecules that capture photons and transfer the harvested light energy to the second component named the reaction center, which possesses Chl a molecules in a matrix of protein.
How are photosystem 1 and 2 connected?
Photosystem I is located on the outer surface of the thylakoid membrane and is bind to the special reaction center known as P700, whereas PS II is located on the inner surface of the thylakoid membrane and the reaction center is known as P680.
What connects the light reaction with the Calvin cycle?
The first electron transport chain in the light reactions connects the photosynthesis and the second chain ends in the production of NADPH. ATP (from light reaction) is used to power the other steps of the Calvin cycle.
What are the 7 steps of light dependent reactions?
Terms in this set (7)
- (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.
On which side of the membrane do H+ ions build up?
The H+ ions build up inside the thylakoid. Electrons move on to photosystem I. In photosystem I, chlorophyll and other light-absorbing molecules in the thylakoid membrane also absorb energy from sunlight.
How are photosystem I and II similar and different?
How photosystem I and photosystem II similar? In photosystem II, energy is absorbed by electrons, creating high-energy electrons which are passed on to the electron transport chain but in photosystem I the electrons are picked up by NADP to form NADPH.
What two main products result from photosynthesis?
Photosynthesis is the name given to the set of chemical reactions performed by plants to convert energy from the sun into chemical energy in the form of sugar. Specifically, plants use energy from sunlight to react carbon dioxide and water to produce sugar (glucose) and oxygen.
What are the two roles of water in the light dependent reaction?
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. These electrons move through structures in chloroplasts and, by chemiosmosis, make ATP.
What is the difference between ps1 and ps2?
Photosystem I (PS I) and photosystem II (PS II) are two multi-subunit membrane-protein complexes involved in oxygenic photosynthesis. The main difference between photosystem 1 and 2 is that PS I absorbs longer wavelengths of light (>680 nm) whereas PS II absorbs shorter wavelengths of light (<680 nm).
What is the purpose of photosystem 2?
Photosystem II (PSII) is a multi-component pigment-protein complex that is responsible for water splitting, oxygen evolution, and plastoquinone reduction.
What happens in photosystem II?
Photosystem II is the first link in the chain of photosynthesis. It captures photons and uses the energy to extract electrons from water molecules. As these electrons flow down the chain, they are used to pump hydrogen ions across the membrane, providing even more power for ATP synthesis.
Why is the Calvin cycle important to most ecosystems?
The Calvin cycle is a process that plants and algae use to turn carbon dioxide from the air into sugar, the food autotrophs need to grow. Every living thing on Earth depends on the Calvin cycle. Plants depend on the Calvin cycle for energy and food.
How do the light reactions produce ATP?
The Light Reactions of Photosynthesis. Light is absorbed and the energy is used to drive electrons from water to generate NADPH and to drive protons across a membrane. These protons return through ATP synthase to make ATP.
What is CO2 fixation?
Carbon fixation or сarbon assimilation is the process by which inorganic carbon (particularly in the form of carbon dioxide) is converted to organic compounds by living organisms. The compounds are then used to store energy and as structure for other biomolecules.