February 21, 2019 | David F. Coppedge

More Wonders to Be Thankful For

Things going on in your body should put believers in chance to shame. Read and be awestruck.

Cochlear outer hair cell horizontal top connectors mediate mature stereocilia bundle mechanics (Science Advances). If you can hear, praise God and don’t take it for granted. This quote is hard to understand, but we give you just a small taste of what is involved in hearing to arouse awe. Read the rest of the open-acess paper if you dare.

Sensory hair cells of the inner ear are active mechanosensitive machines that transform sound-induced mechanical vibrations into electrical signals. The sensory epithelium of the cochlea, the organ of Corti, has two types of sensory hair cells, the inner and outer hair cells (IHCs and OHCs, respectively). IHCs are genuine sensory cells that transmit information via the cochlear nerve fibers to the brainstem auditory nuclei. In contrast, OHCs, which are endowed with electromotility, constitute the cochlear amplifiers that contribute to the detection of weak sound-induced vibrations. The organ of Corti sensory epithelium is positioned between a sheet of paucicellular connective tissue, the basilar membrane, and an acellular gel, the tectorial membrane (TM). Sound-induced vibrations of the basilar and tectorial membranes stimulate the mechanosensitive sensory cells’ stereocilia bundles. The mammalian stereocilia hair bundles of OHCs are arranged in three rows of graded height and are tightly interconnected….

Tissue self-organization based on collective cell migration by contact activation of locomotion and chemotaxis (PNAS). Do you take tissues for granted? We have skin, muscle, bone, and numerous other cell types that bind together into coherent organs with vital functions. But how do they come together in the embryo? How does an individual cell know where to go? These scientists had trouble figuring that out in an amoeba! How much more difficult would it be to explain in the human body? It must be much more complex than simple cell-cell contact. How do cells form tubes, as in the blood vessels and digestive tract? How do particular organs within tissues form, like hair follicles?

Migration of cells as a group is pivotal to the making of various tissues in developing embryos; however, their complexity hinders one from identifying the exact rules. We exploited relatively simple and conditional multicellularity of the social amoeba Dictyostelium to analyze tissue patterning from bottom up by identifying the navigation rules at the individual cell level. We uncovered a guidance mechanism directed by cell–cell contact which gives rise to collective migration and competes with diffusive attractant molecules. Competition of the two directional cues forms the basis of how cells position themselves in the multicellular aggregate according to cell type.

Once seen as nerve cells’ foot soldier, the axon emerges as decision-maker (Science Daily). Even cells that didn’t seem that important are turning out, under more investigation, to be “smarter” than scientists thought. “As far as cells go, neurons are pretty weird,” Harvard neurologists remarked. Here’s why they were surprised at what they found. Think of a complex military system:

The greatest surprises came from auditing the neuron’s growth cones — the outermost tips of the axonal tentacles, which develop into the signaling synapses. This portion contained much of the molecular machinery of an independent cell, including proteins involved in growth, metabolism, signaling and more.

This finding, Macklis says, challenges the dogma that the nucleus and cell body are the control centers of the neuron. Instead, it proposes a more intricate web of decision-making and the existence of semi-independent units far from central command.

“What our results suggest is that growth cones are capable of taking in information from the outside world, making signaling decisions locally, and functioning semi-autonomously without the cell body,” he said. “It’s a whole new way of thinking about neurons.

The only thing evolving is “The team’s findings, described Jan. 17 in Nature, [which] add yet another twist in the ever-evolving understanding of the nerve cells that make up our brains.” The article about tissue organization only briefly suggests a just-so story about “convergence” unexpected by the Darwinians. Once again, we see that the more detail is reported, the less the talk about evolution.

Application

The Cost of Isolation from Creation Is Dangerous: Have You Been Outside Today? (CNS News). John Stonestreet, editor of Breakpoint, wrote a good article stressing the physical, mental and spiritual benefits of stepping outside into creation. He mentions how many times the Bible teaches from nature. “Faced with this forest of references,” Stonestreet says, “it’s hard to see how someone who never spends time outside could fully grasp things the Scripture wants us to…. Thankfully, there’s a simple solution: Go outside!”

John Stonestreet’s article is good on many levels. Read it and apply it. If you are an evolutionist, you should be ashamed of yourself for thinking that these wonders came about by chance (the Stuff Happens Law).

 

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