How does photorespiration protect from Photoinhibition?
Photorespiration Coupled With CO2 Assimilation Protects Photosystem I From Photoinhibition Under Moderate Poly(Ethylene Glycol)-Induced Osmotic Stress in Rice. Photorespiration coupled with CO2 assimilation is thought to act as a defense system against photoinhibition caused by osmotic stress.
What is responsible for the process of photorespiration in c3 plants?
Sometimes in C3 plants, RuBisCO binds to oxygen molecules and the reaction deviates from the regular metabolic pathway. The combination of RuBP and oxygen molecules leads to the formation of one molecule of phosphoglycerate and phosphoglycolate. This pathway is called photorespiration.
What is Photooxidation in plant?
High intensity of light can oxidize the chlorophyll due to which chlorophyll loses its ability to photosynthesize. This can occur due to: Exposure of plants to UV rays of the sun. Donation of energy directly towards oxygen.
What is the role of photorespiration in plants?
Photorespiration plays an important role in the regulation of photosynthetic electron flow under fluctuating light in tobacco plants grown under full sunlight. Plants usually experience dynamic fluctuations of light intensities under natural conditions.
How is Photorespiration Photoprotective?
Therefore, photorespiration has the potential to promote the oxidation of PSI under excess light energy. The highly oxidation of PSI suppressed the donation of electrons from PSI to O2, and, thus prevented oxidative damage to PSI [45]. Accordingly, photorespiration might alleviate PSI photoinhibition under FL.
What is the mechanism of photorespiration?
Mechanism of photorespiration: Photorespiration occurs usually when there is high concentration of oxygen. Under such circumstances, Rubisco, the enzyme that catalyses the carboxylation of RuBP during the first step of the Calvin cycle, functions as an oxygenase.
Why is photorespiration not good for C3 plants?
Photorespiration is bad for C3 plants because this process causes a decrease in the productivity of a plant, hence it is also called the wasteful process. Photorespiration is a respiratory process in many higher plants. This is also known as the oxidative photosynthetic, or C2 photosynthesis or carbon cycle.
What protects chlorophyll photooxidation?
Carotenoids play an important role in protecting chlorophyll from photo damage as it absorbs light energy for use in photosynthesis.
What is the difference between photooxidation and Photorespiration?
Sometimes, high light intensities oxidise the chlorophyll, hence inhibits the rate of photosynthesis. This phenomenon is known as photo-oxidation. On the contrary, the process of uptake of oxygen and production of carbon dioxide in light by photosynthesizing tissue is called photorespiration.
What is photorespiration and what is its effect?
Photorespiration is the oxygenation of RuBP by RUBISCO followed by photorespiratory glycolate metabolism. Competition between O2 and CO2 reduces the rate of carbon assimilation, energetic efficiency of photosynthesis, and may reduce the photosynthetic quotient (PQ = O2 produced/CO2 assimilated).
Why is photorespiration more of a problem for a C3 plant when its stomata are closed?
Why is photorespiration more of a problem for a plant when their stomata are closed? Oxygen levels increase from photosynthesis and compete with carbon dioxide for rubisco’s active site. Carbon dioxide levels increase from photosynthesis and compete with oxygen for rubisco’s active site.
Why is photorespiration more of a problem for a c3 plant when its stomata are closed?
What happens during photorespiration?
Photorespiration is a metabolic pathway that occurs in photosynthetic organisms and releases carbon dioxide, consumes oxygen, and produces no chemical energy or food. This process limits the growth rates of plants.
What is photorespiration why it happens?
How does photorespiration reduce the output of the Calvin cycle?
Photorespiration requires ATP and releases carbon dioxide which contains the carbon that was fixed in the Calvin cycle, so it reduces the output of the Calvin cycle.
Why photosynthesis in C4 plant is more efficient than that in C3 plant?
C4 plants are more efficient than C3 due to their high rate of photosynthesis and reduced rate of photorespiration. The main enzyme of carbon fixation (Calvin cycle) is RuBisCO, i.e. ribulose bisphosphate carboxylase oxygenase. It has an affinity for both CO2 and O2.
Which of the following prevents the photooxidation and destruction of chlorophyll?
The phycocyanins and phycoerythrins effectively absorb light over range of wavelengths that cannot be absorbed by chlorophyll. Thus, they prevents chlorophyll from long and direct illumination and also from its photo oxidation.
Which of the following pigment prevent Photooxidation?
Answer and Explanation: The photo-oxidation and destruction of chlorophyll in plants and algae are prevented by the presence of photosynthetic pigments, like carotenoids…. See full answer below.
How do accessory pigments prevent Photooxidation?
Answer. Continuous oxidation damages the pigment. Thus the accessory pigments (or antennae complex) momentarily supply electrons to the reaction centre chlorophyll a till it gets electrons from water splitting in OEC. HOPE IT IS USEFUL .
How is photorespiration in C3 plants a advantage for them?
How is photorespiration in C3 plants a advantage for them? Plants need to absorb light for photosynthesis but as light can be potentially very harmful to plants if they absorb too much. Photorespiration can act as a defence mechanism against the harmful effects of sunlight.
Is photorespiration a good defence mechanism for photosynthesis?
PLANTS absorb light for photosynthesis but as light can itself be dangerous to plants, they need to protect themselves against its damaging effects. Here we show that photorespiration can act as such a defence mechanism.
Is photorespiration a win from a carbon fixation standpoint?
Photorespiration is definitely not a win from a carbon fixation standpoint. However, it may have other benefits for plants.
What happens to photorespiration when the stomata are open?
When a plant has its stomata, or leaf pores, open diffuses in, and water vapor diffuse out, and photorespiration is minimized. However, when a plant closes its stomata—for instance, to reduce water loss by evaporation— from photosynthesis builds up inside the leaf. Under these conditions, photorespiration increases due to the higher ratio of to .