Amazing Neurons
Seems like you can’t turn on the TV and escape the frequent advertisements for Prevagen, a supplement made from jellyfish that is supposed to help improve memory. Of course, memory is part of our nervous system, located in the brain. Welcome to the world of neurons, the building blocks of our nervous system.
Consider a term (I just made up): Elegance Scale (ES). I often think of the ES in relation to the evolution vs Intelligent Design (ID) discussion. Most people accept the contributions evolution has made to help understand life processes; I’d label this the low end of the ES. At the upper end of ES is extreme elegance, a description for design and complexity that seems to have passed through a threshold well beyond anything evolutionary natural theorists could imagine, some might even classify as supernatural, or “irreversible complexity” in ID vernacular. Let’s take a closer look at neuron cells, and see where they might fit on the Elegance Scale.
NEURONS
Above is a highly simplified schematic of two nerve cells or neurons; the presynaptic cell (left) has received some information, which it will process and transmit to the postsynaptic cell (right). These represent a lattice of billions of interconnected nerve cells scattered throughout the body. Like any other cell in the body, at its core is a containment area known as the soma, which holds various cell organelles (nucleus, membrane, mitochondria, etc.) necessary for health, function, and reproduction.
Protruding out from the soma are tens of thousands of treelike spines called dendrites. Each dendrite is like a lock, waiting for a key – in this case, the key is a chemical neurotransmitter, sent to it from a nearby neuron. Neurons are electrically excitable cells, thanks to electrochemical processes that take place across their membranes when the chemical signals, arriving from the thousands of dendrites, cause concentration differences in positively charged sodium, potassium, and calcium ions. This charge difference sets up a voltage across the membrane that activates a set of proteins called ion pumps.
At a location on the soma, called the Axon Hillock, the chemical information arriving from the dendrites via ion pumps is interpreted and converted into electrical impulses. These pulses are then “fired” through an elongated fiber called the axon. The axon, which can range in length from a fraction of a millimeter to three feet, transmits the electrical information away from the cell body to thousands of terminal endings called buttons.
Picture a narrow gap, known as the synapse, between each button and an awaiting dendrite from a nearby neuron; this space is filled with an extracellular medium full of sacs that contain a variety of neurotransmitters. Electrical pulses from buttons signal sacs of neurotransmitters floating in the extracellular medium to release their contents. There are six types of neurotransmitters: amino acids; peptides; monoamines; purines; gasotransmitters; and acetylcholine; within each of the six “types” of neurotransmitters are a variety of different molecules, each acting as keys searching to unlock a dendrite.
Are you totally overwhelmed with facts yet; okay, I’ll stop? I have just described, in simplest terms, the anatomy and function of neuron cells, a miniscule glimpse into a far more complex microbiologic world. Can you imagine all this evolving from only natural processes? Can you imagine billions of neurons firing simultaneously like a great orchestra in your brain, capturing a thought and then committing it to action or memory? I can’t. Even hard-core naturalists have begun to admit that neurons, and their elegant systems, seem to point to “design”, but they aren’t yet ready to give credit to our Creator, the ultimate Intelligent Designer. Their only recourse is the old, tired argument that “given enough time, natural science will find an answer and fill this gap.” For me, this is a glimpse into the mind of our God.
