Answer and Explanation:
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The experiment done by Meselson and Stahl demonstrated that DNA replicated semi-conservatively, meaning that each strand in a DNA molecule serves as a template for synthesis of a new, complementary strand. Although Meselson and Stahl did their experiments in the bacterium E.
The air spaces occur in Spongy mesophyll tissue.There are large spaces in a leaf because it is for storing water and carbon dioxide which will be used for photosynthesis. The large air spaces are usually found in the spongy layer of the mesophyll. The arrangement of this spongy mesophyll facilitates the movement of gases through the mesophyll. Directly beneath each stomate at the leaf surface there is usually a small air space, called a stomatal chamber, where no mesophyll cells are present. This also aids in gas exchange.
The most common felsic rock is granite. Common felsic minerals include quartz,muscovite<span>, </span>orthoclase<span>, and the </span>sodium<span>-rich </span>plagioclase feldspars<span>. In terms of chemistry, felsic minerals and rocks are at the other end of the elemental spectrum from the mafic minerals and rocks.</span>
The answer is that the criteria of classification change whith the improved understanding of organisms around us