Studies of both animals and humans have shown that sex hormones somehow affect the stress response, causing females under stress to produce more of the trigger chemicals than do males under the same conditions.
This concentration gradient is extremely important for setting the resting membrane potential of excitable cell membranes, which is needed for normal contraction of smooth, cardiac, and skeletal muscle.
Similar studies tested whether students learned basic physics and chemistry concepts better by reading plain text or viewing pictures too and everyone do better with the help of pictures.
The energy density of lithium batteries has come a long way in the past few decades, but the chemical reaction on which they rely will never be able to match the energy available from the metabolisation of glucose.