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Remote Ready Biology Learning Activities has 50 remote-ready activities, which work for either your classroom or remote teaching.
Perpetual Propagation Machines and Energy
The first rule of thermodynamics is that "energy can neither be created nor destroyed", but is instead continuously reallocated, to the ground, to the air, from one organism to another, from one atom to another; all life, it would thus seem, is one giant game of pass the potato, the "god-machine" a giant perpetual motion device of which all materials of existence are apart. This is true of all energy whether chemical, or electrical. We have spent a good deal of time discussing what an Action Potential is like and how one can manipulate its propagation, and pondering how one identical signal can produce an infinite number of outcomes. In class we have discussed how an action potential can be "passed" on from one battery to another, but we have not yet discussed where the action potential (the very first one in the line of propagation), in terms of the energy that it is, comes from. What initiates the first action potential in an axon (changes in membrane potential due to the presence of neurotransmitters?--what of the very first axon to generate the action potential---how do the sensory neurons in the eye for example generate an stimulus induced action potential---what in the stimulus triggers the depolarization of the cell?), where does this source of energy come from. It must already be there somewhere in the cell and in the body, from the food we eat to the cells perhaps, but in other instances, such as the beginning of embryonic development the initial depolarization that sets the whole process of creating you (the first spark of energy taken in--the first change in cellular potential) does not hail from a dietary source, or even from a nervous system, but from the depolarization and change in membrane potential of an egg cell by a sperm cell---are we then, when philosophizing in terms of action potential = energy, somehow continuously propagating these initial potential changes throughout our lives, are we then (since the catalysis for these energy changes came from our parents) perpetuating an action potential of some kind from our parents, from our ancestors?