We've all done these things in school. You get a piece of paper, for a test, that has a picture of a circle, with things floating inside of it, and lines coming off each part of what's depicted. In this case its a cell. So you write the name of each organelle, membrane, Golgi apparatus (perfect terminology there), and what have you, and when the blanks are filled, you raise you hand, having passed the test. Unless you simply filled in the ones you didn't know with your favorite rugby players.
When I was young that's how I viewed all aspects of the body (and organisms in general.) When I touched you, you were really a kind of solid cartoon, virtually never, until I was older, providing me tactile clues as to how your body works, and what's going on under your skin. And that's for the best... given my rich confusion about far more obvious matters (and more relevant ones to a normal existence as well.)
When I touched my arm only only imagined dimly that it had anything at all to do with cells, or even muscles, really. Surface was, and to a great extent it must continue to be, everything.
For a long time I have been young enough to look at things somewhat fresh, and with a sort of naive astonishment. It is the privilege of the young to do this (though as I reminded a friend of mine, who's comments were reminding me how old we are, my privileges are running out.)
I'll never forget a wonderful drive home I had seven years ago, to Elletsville, where I lived with some punk rock kids and two little girls: Ona and Florence. I had just bought my girlfriend the new Dixie Chicks album, and had plans with her that night for her birthday. I had been working at the Bagel Bakery that morning, then come home and taken a nap and dragged myself about of bed (poor guy had to do something nice for his fetching girl...) to go to the bookstore and buy the present, then come home, clean up, and take her to dinner. Having had a cup of coffee (from the bookstore) and feeling the anticipation of her pleasure and joy at my attentions, my mind was wandering pleasantly as I turned onto Ratliff road, my road, and climbed the last hill in the whitish late afternoon sunlight of autumnal equinox.
I looked out at a hillside, for Elletsville is thick with beautiful examples, and saw the expected beauty that the late afternoon sun so regularly produces for those with the eyes to see it. Something seemed odd though. A part of my brain went back to a time in the early '90's when I noticed, while working for Orkin Pest Control, one day, that the shadows of the grass and tree's seemed doubled, or something, like an extra, dimmer sun had passed overhead. To this day I can't say exactly why it seemed like that, but I remember extremely clearly pulling into an auto body shop and asking for a welding mask to look at the sun. While waiting I punched a hole in a piece of paper and saw the image of the sun being slightly occluded by a round object, projected onto the back of my hand. The very nice proprietors of the auto body shop, fascinated to say the least by this mad bug guy, came out and gave me the mask, I glanced up at what I already had seen, then gave the mask to the proprietor, and we grinned with mutual admiration at our pipsqueak lives, full of Wheaties, work and top forties tunes, and rarely touching in any sense on the sun and the moon.
Something about the light, as I drove up that hill on Ratcliff road reminded me of that partial eclipse in the Spring of 1994. But, even as I smiled at the memory, I knew that it wasn't a change in the sun, but something about the quality of the appearance of the grass... I just looked at it one more time, and then looked across the street to the east and saw something different, something different in the appearence of that grass. Whereas the grass on the west side, between me and the sun had a kind of stained glass quality, the grass on the east side, reflecting the sun (the light of which was passing over my car and I) back into my eyes, had a buff, almost arid quality.
The grass on the western side was not reflecting light much at all, from what I could tell. "My God," I said to myself, "it's glowing." I wondered, rather dumbly, how long it had been doing that right before my eyes. So, I realized for the first time, grass accepts some percentage of light, and lets it pass right through, just like stained glass. Everywhere I looked, for about 180 degrees from the seat of my vehicle, there was, an aspect of the landscape that was not reflecting the sun, but transmitting it.
Photographers know all about the strange tricks of light, and probably know an additional thousand details about the way to look at things, when looking and choosing is your bread and butter.
But biologists and chemists and physicists know all about why things look the way they do. And in the next few posts, along with that test that you took in school about the way cells are constructed, or at least we were taught they were, I'd like to sing a little body electric, and make an even better case for the Church with the finest wrought windows: 'cus these windows were made for the sun.
Turns out that our little Test that we took of the cell is fine, if you only want to know some of the things there are to know about what's happening in a cell. Back when I was a kid, most biologists had some pretty straightforward training as to how to identify the various proteins and lipids and enzymes that made up the interior of the cell. They blended up the cell, and extracted from the smoothie what they could, then purified it, and studied it. As science has probably shown you: this method has worked marvelously. We know an astonishing amount of stuff about the nature of the molecules that comprise our bodies. It wasn't easy, but scientists have painstakingly figured a lot of our building blocks out.
There are a few details, however, that the Osterizer setting #7 (liquify) might have not helped much with. For example: what is the nature of the spaces in between the organelles and within the membrane of a cell. Typically, as a kid, I just labeled it cytoplasm, a term meant to sort of conjure the space for everything that wasn't a nucleus or organelle: I don't know, proteins, water, and the kitchen sink, or what have you. Everyone I ever talked to about it seemed to believe it was about two kitten whiskers to the side of salt water. Plus some enzymes and stuff.
And for most of my life, most people, for the most part were happy with such a picture. Painter philosophers (and half drunk art lovers) love to point out that the canvas makes a significant contribution to the mature accomplishment of a painting, and one could hardly be accused of rudeness for simply reasoning that the "white space" in a cell was sitting there keeping the rest of the cell full, and the organelles and stuff from bumping into one another.
Turns out that blending the cell (and viewing it through microscopes) gave us a ton of valuable info about its building blocks. But, like the difference between a huge pile of bricks, and a house, those building blocks had led us not only to edification: sometimes knowledge can lead you astray.
This is not to say that our understanding of cellular structure is a facile endeavor. As I said before: we have achieved incredible resolution of knowledge about all manner of aspects in Molecular Biology and even the structure of the cell. I recently read about the endoplasmic reticulum, which I am not sure it was pointed out to me as a child, is a system of three-dimensional canals and spaces involved in intracellular transport and occupying a large proportion of the cell volume. That's funny, I had thought that my cells transported nutrients through gross flows of fluid exchanged over gradients of salinity, or what have you. Canals transporting water? In a cell? I found that rather surprising. But then, after a learned a few more things, I found it, like I find mycelium, engrossingly delicious.
According to a book I am currently enjoying immensely, The Rainbow and The Worm, (The Physics of Organisms) by Mae-Wan Ho, until recently most biologists regarded the organelles of a cell to be comprised mostly of inert structural proteins, and the cytoplasm to be richly endowed with dissolved proteins and enzymes, floating randomly until plucked by the cell's metabolism for use. The exceptions to this scenario involved respiration and photosynthesis, but basically the cytoplasm was regarded as a reservoir of sorts.
Further investigation has recently shown that the proteins thought previously to be dissolved in cytoplasm, are in fact complexed into into intricate structures, throughout the "body" of the cytoplasm. These structures, while hardly well understood, are quite a shock to the old concept of storage and warehousing. The structures appear to have some use, and are thought to be in intimate contact with the hydrogen bonds of the cytoplasm water: perhaps, somewhat shockingly, meaning that the proteins play some role in structuring the watery interior of the cell. Far from being in solution (in the typical sense) they form an organized, unified structure, to accomplish some crucial role in the life of the cell. The cytoplam is a structural matrix of protein, enzyme (a type of protein) and water.
Now do you see why blending might have obscured some of the structure of the cell?
Perhaps none of this means much of anything to you. So what? you might be wondering. So their is structure to cytoplasm. "Next time I'll be sure to put some squares and triangles in the white space when I take the test on the structure of a cell. Ok, Andy?" Ok. It's a start.
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