02 May 2014

This is a living creature


I find this photo to be endlessly fascinating.  The creature is a single-cell organism (Nassula).

And it has all that is needed for life.  What is it that converts this combination of membranes and complex molecules into a "living" organism capable of eating and reproducing.  It staggers my mind to think about it.

Photo credit: Mr. Riccardo Taiariol, La Spezia, Italy, using differential interference contrast at 25x, from an Olympus Bioscapes gallery.

15 comments:

  1. I'm always amazed at the parts that are smaller than cells but by technically cells (like the vacuole etc) - how the heck does it all work? I wish I could remember more from primary and secondary school biology. Beautiful picture.

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  2. Actually, a cell can make do with way less. The nucleus and mitochondrion are modern advances that bacteria don't have: http://www.biology4kids.com/files/micro_prokaryote.html

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    1. And at the risk of a Pythonesque discourse on who's poorer (or in this case, smaller and simpler), what of the wee bit viruses...

      Are they technically not alive until they latch on to something; are they in stasis like seeds?

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  3. It is amazing. Seeds also fascinate me. How does the life "come back" after you dry a corn seed, freeze it, then stick it in the ground? It's mind boggling.

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  4. This fellow is large. For one thing, as Bridget Magnus mentioned, it's a eukaryote, which already makes it much bigger and more complex than the majority of species of living organisms on earth - that is, bacteria and archaea. I'd estimate that this cell is around 200 μm long - in comparison, an E. coli is around 2 μm long, and it's hardly the smallest bacteria.

    Also, the visible internal structures are not what they might look like - they're all vacuoles containing food. The oblong thing that you thought was a mitochondrion is probably a fragment of a filamentous colony of cyanobacteria, perhaps Nodularia. The big round vacuole contains some unidentifiable junk. The nucleus is not visible in this photo, probably just out of focus (remember that regular microscopes have very shallow depth of field). It might be in the somewhat different looking cloudy area to the left of the big round vacuole, but I couldn't tell for certain. A cell like this would have many - probably hundreds or thousands - of mitochondria, all of them too small to make out (in the 1 μm range).

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    1. Thanks, bucaneer. I've deleted my speculation from the post. But of course I still retain my awe.

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  5. I think the question you ask in your post is one of the fundamental questions of mankind.

    Notice that the moment the “spark of life” disappears, entropy kicks in and the tendency toward randomness takes over. And how quickly disorganization occurs, witness the rapid decomposition of a body after eighty years of fantastic organization. What organized it in the first place? What constitutes that force which causes random matter to organize into a living being?

    A house cannot build itself, nor an effect cause itself.

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    1. In this organisms case, presumably solar energy as the driving force, though some extremophiles would make use of geothermal energy.

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    2. Well I guess you've answered your own question. Regardless, I share your sense of awe.

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  6. http://www.iflscience.com/chemistry/metabolic-reactions-could-have-occurred-formation-life

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  7. In the beginning God ....

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  8. I got just enough into cell biology to see it stretch out into the distance, all the complexity and electrochemical interactions beyond. May be small, but not simple.

    And the line between alive and not alive yet is only in our minds, like what separates Man from Animals. Which is to say, nothing really.

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  9. I, too, share your awe!
    "In the beginning was the Word, and the Word was with God, and the Word was God. The same was in the beginning with God. All things were made by him; and without him was not any thing made that was made." John 1:1-3
    "Through faith we understand that the worlds were framed by the word of God, so that things which are seen were not made of things which do appear." Hebrews 11:3
    "For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether they be thrones, or dominions, or principalities, or powers: all things were created by him, and for him: And he is before all things, and by him all things consist." Colossians 1:16,17

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  10. It's funny that some people still want to believe the idea that, instead of these creatures occurring as a result of natural forces over a very long period of time, a creator took the trouble to design and create each and every one of the thousands of species of micro-organisms, and also put countless millions of fossilised animals and plants IN stone, and that this very same creator completely ignored the fifty or so millions of humans living, as just one geographical example, about 2000 years ago in what is now China and sent His Son to the middle east, speaking Aramaic, to save us all. He later did the same thing with Mohammet, born into a society with a small population, speaking Arabic, to save us all.

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  11. Stan, you might be interested in this documentary http://www.sbs.com.au/ondemand/video/234273859563/Life-On-Us-Ep2

    After the first ten minutes or so, it got really interesting and went a long way to explaining how and why our modern society has such "diseases" as gluten intolerance and why our teeth are so bad compared to humans in the past.

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