Vibration theory of olfaction have a vibrational energy mode compatible with the difference in energies between two energy levels on the receptor, so electrons can travel through the molecule via inelastic electron tunneling, triggering the signal transduction pathway. The vibration theory is discussed in a popular but controversial book by Chandler Burr. The odor character is encoded in the ratio of activities of receptors tuned to different vibration frequencies, in the same way that color is encoded in the ratio of activities of cone cell receptors tuned to different frequencies of light. An important difference, though, is that the odorant has to be able
Edible protein per unit area of land Edible protein per unit area of land Edible protein per unit area of land is a measure of agricultural productivity. This measure for various major foodstuffs is shown in the chart below. Values are expressed for one calendar year. Biological values and usable protein values have been added to the chart to show the true relative value of each foodstock for human consumption. Usable protein values are determined by the biological value (BV) of each foodstuff and represent the amount of protein that is fully digested by humans, it is calculated as follows: Soybeans produce at least two times more