Plants, green color

As a general rule, photosynthesis occurs in a plant s leaves. The leaf contains chlorophyll, which reacts when sunlight strikes the leaf. It is also the chlorophyll which gives the leaf its typical green color, since photosynthesis absorbs most light rays except green, which are reflected outwards. 

Avoid the use of tobacco if you grow tomatoes, peppers or Irish potatoes. Tobacco coutaius tobacco mosaic viras (TMV) which will get ou your hands and be spread to plants which you touch. Equipment, insects or anything touching an infested plant and then another plant is also likely to transfer the disease from plant to plant. TMV is very hard to control and reduces both fruit set and fmit size. Total yield of TMV-infested plants may be reduced slightly or nearly wiped out. Leaves of infested plants may be distorted and will probably have a mottled appearance rather than a solid green color. Remove isolated plants showing these symptoms as soon as they appear. 

Lavoisier said that Phosphorus is met with in almost all animal substances and in some plants which, according to chemical analysis, have an animal nature.. . . The discoveiy that M. Hassenfratz has made of this substance in wood charcoal would make one suspect that it is commoner in the vegetable realm than has been thought tins much is certain that, when properly treated, entire families of plants yield it (37). Apothecary J. K. F. Meyer of Stettin wrote in 1784 that he had observed, several years previously, a permanent green color in the essences he prepared by digesting green herbs in copper vessels He concluded that phosphates in the leaves had reacted with the copper to form copper phosphate (38). 

Comparison of color measurements on wheat flour and six different plant-protein products with the visual appearance of these flours shows that the L, a, b scale does yield meaningful values (Figure 3). The L value for the alfalfa leaf protein (L 75.5) shows that this product is much darker than the wheat flour (L = 89.5) and somewhat darker than the other plant-protein materials (L = 79.5 to 88.2). The a values do not show any significant variations (a +1.0 to -1.7), indicating the absence of significant red or green coloration in the flours. 

Chlorophyll The green coloring matter of plants necessary for the process of photosynthesis. 

Many of the colors associated with higher plants (green leaves in the spring and summer, yellow or red leaves in the fall, the orange color of carrots, some colors in flower petals) are due to the presence of pigment molecules such as chlorophylls and carotenoids. In this experiment a mixture of these pigments will be isolated by solvent extraction of plant tissue, separated by chromatography, and the components identified by visible spectrophotometry. 

The pyrrole nucleus has been shown to be present in the complex substances chlorophyll (the green coloring matter of plants), hematm (the red coloring matter of blood), and in the coloring mailer of bile. 

The green color of most plant leaves is the result of absorption of blue and red light by chlorophyll, which reflects almost all of the light in the region around 550 nm, as shown in Fig. 10. 

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