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If your wondering this is the kind of stuff I am reading.
The photosynthetic process occurs in chloroplasts, where the photosynthetic pigment chlorophyll captures the energy from sunlight and converts it into chemical energy. Because of the high absorption of chlorophyll in the top portion of the leaf, a light gradient is created from the leaf surface into the tissue inducing different light regimes. Under strong daylight illumination, the chloroplasts at the surface of the leaf are saturated, such that most of the light cannot be used for photosynthesis, but the chloroplasts in the depth of the leaf are light deprived.31, 32 In ficus plant leaves containing cystoliths, and in pecan leaves containing large calcium oxalate druses, the mineral deposits were proven to have a function in redistributing light into the leaf. Part of the light is scattered through the transparent mineral deposits in the bulk of the leaf, thus reaching the light deprived chloroplasts. This results in an increase in the yield of light utilization.3
In this study, we examine the optical functions of calcium oxalates and silica leaf minerals as an integrated system. Preserving the leaves as close to their natural state as possible, we use micro-computed tomography (microCT) to image the leaf soft tissue and the distribution mainly of calcium oxalates, without fixing the tissue or using other invasive methods.33-35 MicroCT however cannot distinguish silica and soft tissue unless the silica phytoliths are large and relatively thick. It was therefore necessary to develop a different tool for examining the distribution of silica in the leaf. We report here a method to infiltrate the intact leaf with the {2(4pyridyl)-5-[(4-(2-dimethylaminoethylaminocarbamoyl)methoxy]phenyl}oxazole (PDMPO) fluorophore to study in situ the 3D distribution of silica deposits with confocal microscopy. PDMPO is a fluorophore that electrostatically interacts with the silica surface.36 PDMPO was used to investigate silica deposition in diatoms and radiolaria,37-41 and in plants to visualize extracted silica bodies.42 By superimposing the microCT and confocal images, we create a 3D map of the whole leaf showing the distributions of calcium oxalates, silica, and the naturally fluorescing chlorophyll.
The photosynthetic process occurs in chloroplasts, where the photosynthetic pigment chlorophyll captures the energy from sunlight and converts it into chemical energy. Because of the high absorption of chlorophyll in the top portion of the leaf, a light gradient is created from the leaf surface into the tissue inducing different light regimes. Under strong daylight illumination, the chloroplasts at the surface of the leaf are saturated, such that most of the light cannot be used for photosynthesis, but the chloroplasts in the depth of the leaf are light deprived.31, 32 In ficus plant leaves containing cystoliths, and in pecan leaves containing large calcium oxalate druses, the mineral deposits were proven to have a function in redistributing light into the leaf. Part of the light is scattered through the transparent mineral deposits in the bulk of the leaf, thus reaching the light deprived chloroplasts. This results in an increase in the yield of light utilization.3
In this study, we examine the optical functions of calcium oxalates and silica leaf minerals as an integrated system. Preserving the leaves as close to their natural state as possible, we use micro-computed tomography (microCT) to image the leaf soft tissue and the distribution mainly of calcium oxalates, without fixing the tissue or using other invasive methods.33-35 MicroCT however cannot distinguish silica and soft tissue unless the silica phytoliths are large and relatively thick. It was therefore necessary to develop a different tool for examining the distribution of silica in the leaf. We report here a method to infiltrate the intact leaf with the {2(4pyridyl)-5-[(4-(2-dimethylaminoethylaminocarbamoyl)methoxy]phenyl}oxazole (PDMPO) fluorophore to study in situ the 3D distribution of silica deposits with confocal microscopy. PDMPO is a fluorophore that electrostatically interacts with the silica surface.36 PDMPO was used to investigate silica deposition in diatoms and radiolaria,37-41 and in plants to visualize extracted silica bodies.42 By superimposing the microCT and confocal images, we create a 3D map of the whole leaf showing the distributions of calcium oxalates, silica, and the naturally fluorescing chlorophyll.
