Rice grain different parts

Comparative Studies on the Cell Wall Polymers Obtained from Different Parts of Rice Grains... 

Figure 1. Scanning electron micrograph of the cell wall preparations obtained from the different parts of rice grain (7). Caryopsis coat (upper left), aleuron layer (upper right), germ (lower left) and starchy endosperm (lower right). Bars in the picture indicate 5 /zm.

While the hemicelluloses obtained from the germ, aleuron, and caryopsis coat cell walls all showed a similar monosaccharide composition, this was not the case for the endosperm tissue. Thus, a major difference in the structure of hemicellulosic polysaccharides exists between the preparations obtained from the endosperm cell walls and those from the cell walls of the other parts of the grain, i.e., rice bran. (Rice bran consists of the caryopsis coat, aleuron layer and germ.) Comparison of the detailed structural features of the hemicellulosic polysaccharides of endosperm and bran cell walls will be discussed in the following sections. 

The primary use of tantalum metal is in making capacitors. A capacitor is an electrical device similar to a battery. It can be given an electrical charge, which it then stores until needed. Capacitors are essential parts of nearly all electrical circuits. Semiconductor circuits, like those used in transistors, require tiny capacitors the size of grains of rice. Tantalum is one of the best metals for this purpose. Different kinds of capacitors are made for many different applications. They are used in military weapons systems, aircraft, space vehicles, communication systems, computers, and medical applications. For example, the smallest hearing aids are likely to have a tantalum capacitor. 

Examples of matter range from grains of rice to the stars, from a drop of water to the rocks of the Grand Canyon, from a potato chip to a computer chip. It s all the stuff around us—all part of the same puzzle. You know that aU these bits of matter connect in some way, just like the pieces of a jigsaw puzzle. But, there are so many different sizes and kinds of matter. How can you begin to make sense of the puzzle of matter ... 

Plant protein sources provide 65% of the world s supply of protein, with cereal grains (47%) and pulses, nuts and oilseeds (8%) as the other major sources. Of the cereals, wheat (43%), rice (39%) and maize (12%) are the main contributors. Other limited sources of plant protein are fruits, leaves, tubers and other parts of plants included under the terms fruits, vegetables or root crops. Plant protein sources can differ from animal protein sources in terms of digestibility, amino acid composition, the presence of antinutritional (such as enzyme inhibitors) and toxic factors (e.g. saponins, cyanogens and lectins), which adversely influence protein digestibility, nutritional value and food safety. 

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