Breastfeeding Your Man

C4 Rice

Evolution does not only causes visible changes. Changes in size or color of a living being can be very spectacular, but the internal changes can be much more prominent. Of these, changes in the mechanisms associated with photosynthesis are especially important for our planet. Paraphrasing

Paleofreak , can be defined evolution natural selection as differential reproduction of a combination of genes. If some genes provide an advantage to their possessors, it facilitates the next generation has a greater proportion of individuals who share these genes and reduced the rest. For example, if a hunter is more effective because it is faster, get more food and will leave more descendants.

In case of photosynthesis, plants have developed three alternative mechanisms, each tailored to a different environment. The variation is in the form of retain and use the CO 2 . The oldest method is called via three carbon. It works very well. While this expanded massively and 95% of the plants use. Is the preferred method when you have abundant nutrients, water, CO 2 or sufficient nitrogen and moderate temperatures.

A second method is known as the road four carbons. Is more complex and uses some different molecules. A change is more effective and advantageous when the plant is in conditions of scarcity of water, nitrogen or CO 2 . Although representing only 5% of the plants is used by some as important as corn or sugar cane.

The third method is known as Crassulaceae acid metabolism in honor of the family of plants where it was discovered. Its advantage is that it minimizes water consumption and that is usually found in desert environments. All plants get carbon dioxide from the atmosphere through some holes in the leaves called stomata . But in this exchange, the plants lose water, a valuable resource and, in some situations, limited. To minimize losses and retain these plants capture CO 2 night. By day it is released to participate in the process of photosynthesis. Such plants typically lose 50 to 100 grams of water per gram of CO 2 retained, compared to 250 to 300 grams of the four-carbon pathway and 400 to 500 grams of the route of the three carbons.

At the end there are several paths to success. And evolution is "survival of the strong", rather a small advantage to the fittest. Of course the man's hand may also intervene in this process. At this time many teams work throughout the world to try provide rice plants the genes responsible for the four-carbon pathway . It aims to improve the performance of rice production by 15 to 20 percent. Hopefully this is the best way.


Category: Biology