What is photoinhibition in photosynthesis?
Photoinhibition of photosynthesis is defined as a persistent decrease in the efficiency of solar energy conversion into photosynthesis in combination with a decreased overall capacity for photosynthesis.
What is the relationship between photorespiration and photosynthesis?
The main difference between photosynthesis and photorespiration is that the photosynthesis occurs when RuBisCO enzyme reacts with carbon dioxide while the photorespiration occurs when RuBisCO enzyme reacts with oxygen. Furthermore, photorespiration reduces the efficiency of photosynthesis.
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.
Does photorespiration help photosynthesis?
There’s some evidence that photorespiration can have photoprotective effects (preventing light-induced damage to the molecules involved in photosynthesis), help maintain redox balance in cells, and support plant immune defenses 8start superscript, 8, end superscript.
Why is photoinhibition important?
Photoinhibition, defined as the inhibition of photosynthesis caused by excessive radiance, affects field production to a great extent. This phenomenon is particularly relevant in refores- tation practices, when one deals with forests of rapid growth such as Eucalyptus.
Is photorespiration part of photosynthesis?
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 the difference between photorespiration and respiration?
Hint: Respiration is the process in which intake of oxygen and release of carbon dioxide happen and photorespiration is the process in which the enzyme RuBisCo oxygenates RuBP by wasting the energy produced by photosynthesis.
Which of the following is required both in the process of respiration as well as photosynthesis?
Hint: Both respiration and photosynthesis synthesise ATP therefore both require the transfer of electrons with the help of those substances that help in the synthesis of ATP.
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.
What is the importance of photorespiration?
Photorespiration helps in dissipation of energy where stomata get closed during daytime because of water stress. Photorespiration protects the plant from photoxidative damage by dissipating excess of excitation energy.
What is photoinhibition in phytoplankton?
The decrease in photosynthetic rate under high irradiance may also result from photo-oxidation and other causes, but photoinhibition is usually used to describe the reduction of photosynthetic capacity, independent of gross change in pigment concentration, induced by exposure to high irradiance (Powles, 1984).
What is meant by photoinhibition?
Photoinhibition. Photoinhibition is defined as the light dependent decrease in photosynthetic rate which may occur whenever the photon flux is in excess of that required for photosynthesis (Long et al., 1994), that is, whenever σPSII · I > n · τ–1.
What are the benefits of photorespiration in plants?
However, it may have other benefits for plants. There’s some evidence that photorespiration can have photoprotective effects (preventing light-induced damage to the molecules involved in photosynthesis), help maintain redox balance in cells, and support plant immune defenses.
What determines how frequently each substrate gets chosen for photorespiration?
Binding to oxygen and the initiation of photorespiration is favored at high temperatures and a low carbon dioxide-to-oxygen ratio. What determines how frequently each substrate gets “chosen”? Two key factors are the relative concentrations of and and the temperature.
What happens to photorespiration when a plant closes its stomata?
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 .