Http://blogs.discovermagazine.com/seriouslyscience/2015/01/29/pandas-ancestors-ditch-meat-bamboo/
According to this study, it may have had to do with the deactivation (technically known as “pseudogenization”) of an umami taste receptor gene. Umami is the taste that makes things like meat, soy sauce, and mushrooms extra yummy. Apparently, at some point in panda evolution, the umami receptor became non-functional. Based on how much the gene has changed, the authors calculate that this happened around the same time that pandas started eating bamboo. Whether it’s cause or effect is unclear, although the authors think the switch to bamboo may have happened before the gene was lost. Regardless, the loss of the gene reinforced the panda’s vegetarian diet because it made meat less delicious to the bears.
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Answer:
Aerobic metabolism is the most efficient way of producing ATP; it produces significantly more ATP for each molecule of glucose than anaerobic metabolism. Although the primary source of ATP in aerobic metabolism is carbohydrates, fatty acids and protein can also be used as fuel to generate ATP.
The bonds that hold H2O2 together break apart and the atoms are rearranged to form water (H2O) and oxygen (O2) molecules. This happens slowly in store-‐bought hydrogen peroxide, so even in dark bottles, it will 'expire' in a year, or less if it's opened. ... And higher concentrations of H2O2 produce more oxygen.