Posted on 05/20/2009 9:14:26 PM PDT by GodGunsGuts
Edited on 05/20/2009 9:32:02 PM PDT by Admin Moderator. [history]
White Blood Cells Walk to Infection on Tiny Legs
May 20, 2009
How do white blood cells know where to go when infection strikes? The cells have tiny little feet and crawl like millipedes, against the blood stream, if necessary, following signals from the infection site. When they arrive...
Ping!
Thanks for the ping!
White blood cells?
That’s racist!
*snicker*
Oh yeah, THAT evolved.
Ciliary motion, pseudopodia in algae, all these are among the most rudimentary locomotive mechanisms in single-celled entities.
Cool.
no wonder I’m not sleeping well with all that stomping going on inside me, Yawn.
You didn't read the article, nor the cited articles in that piece.
Next, the scientists turned to the Institute’s Electron Microscopy Unit. Images produced by scanning and transmission electron microscopes, taken by Drs. Eugenia Klein and Vera Shinder, showed that upon attaching to the blood vessel wall, the white blood cell legs ‘dig’ themselves into the endothelium, pressing down on its surface. The fact that these legs – which had been thought to appear only when the cells leave the blood vessels – are used in crawling the vessel lining suggests that they may serve as probes to sense exit signals. The researchers found that the shear force created by the blood flow was necessary for the legs to embed themselves. Without the thrust of the rushing blood, the white blood cells couldn’t sense the exit signals or get to the site of the injury. These results explain Alon’s previous findings that the blood’s shear force is essential for the white blood cells to exit the blood vessel wall. The present study suggests that shear forces cause their adhesion molecules to enter highly active states. The scientists believe that the tiny legs are trifunctional: Used for gripping, moving and sensing distress signals from the damaged tissue.
I think the larger problem is the obvious assumption that the 'most rudimentary locomotive mechanisms in single-cell entities' evolved in the first place. While these may be the 'most rudimentary locomotive mechanisms' we observe, that does not mean that they are simple nor does it mean that they 'evolved'. The poster begs the question by assuming that the "most rudimentary locomotive mechanisms in single-cell entities" 'evolved'. This is logical fallacy, not argument.
Invoking logical fallacies as argument is the real problem here. You will find that error wherever you find the argument that evolution is 'scientific' rather than a philosophical belief.
Echinacea makes WBCs run instead of walk. ;-)
I bet it does. I just hate the taste of it. I know Sassy runs when I try to give her some, lol.
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