Aromatic and Glutinous rice varieties are seen in both Indica and Japonica main types of rice. There are more than 40,000 varieties of cultivated rice (grass species Oryza sativa) said to exist. But the exact figure is uncertain. Over 90,000 samples of cultivated rice and wild species are stored at the International Rice Genebank and these are used by researchers from the world.
Plate Tectonics-Formidable Forces. Plate tectonics is the fundamental mechanism that drives geological processes in the geosphere. Plate tectonic theory is based on an understanding of the Earth's internal structure, the different types of tectonic plates and plate boundaries, and the driving forces of plate movements.Figure 4a): occur where two lithospheric plates move away from each other, driven by magma rising from deep within the mantle. Volcanic activity at a divergent plate boundary creates new lithosphere along what is known as a spreading ridge. Figure 4b: Generalised structure of a convergent plate boundary.
Plate tectonics (from the Late Latin tectonicus, from the Greek: ÏÎµÎºÏÎ¿Î½Î¹ÎºÏÏ pertaining to building) is a scientific theory describing the large-scale motion of Earth's lithosphere. The theoretical model builds on the concept of continental drift developed during the first few decades of the 20th century.