Question

Photo-oxidation of chlorophyll is called as -
a. Intensification
b. Chlorosis
c. Solarization
d. Defoliation

Answer 1

Hint: Chlorophyll may be a green photosynthetic pigment found in plants, cyanobacteria, and algae. Chlorophyll is significant for photosynthesis, which allows plants to soak up energy from light. Chlorophyll mostly absorbs in the form of blue color and red color to a lesser extent of the spectrum, hence its intense color is green.

Complete answer:
Chlorosis may be a disease that is caused by a deficiency of some macro and micronutrients, which causes discoloration of leaves.

Solarization to a decrease or complete disappearance of starch following long exposure of leaves to the light of intensity, that originally was favorable for abundant starch formation. At higher intensities of sunshine, however, pigments get bleached and therefore the process doesn’t work efficiently. The inhibition of photosynthesis by photo-oxidation at higher intensities is named solarization.
Defoliation is that the premature removal of grass parts leaves.

Hence, the correct answer is option (C).

Additional information:
Photo-oxidation means the release of electrons after absorption of a photon occurs during non-cyclic photophosphorylation. It involves an outsized number of chemical reactions. The electron moves from oxidized chl to electron acceptor plastoquinone then further to other electron acceptors making electron transport chain. The oxidized CHL accepts an electron from the donor (H2O) and this leads to the synthesis of molecular oxygen from water.
Chlorophyll trap sunlight during photosynthesis but are destroyed at high candlepower.

Chlorophyll is located within the membrane of thylakoids where they constitute the 2 photosystems (PS I and PS II). The photosynthetic unit (PSU) represents the essential unit of the light-harvesting apparatus and consists of an outsized number of antenna chromophores coupled to an RC.

Note: The light‐dependent generation of active oxygen species is termed photo oxidative stress. this will occur in two ways:
- The donation of energy or electrons on to oxygen as a result of photosynthetic activity.
- Exposure of tissues to ultraviolet irradiation. The light‐dependent destruction of catalase compounds the matter.
Carotenoids play an important role in protecting chlorophyll from photo damage as it absorbs light energy for use in photosynthesis.