Macroxenoglossophobe

Consider the human kidney.

The glomeruli produce an ultrafiltrate of plasma that includes many useful substances in addition to the waste products it is attempting to excrete.

It then attempts to retrieve these useful substances in its proximal convoluted tubules. This process is impaired in individuals that have a genetic or acquired absence or deficiency of appropriate tubular transport mechanisms.
The process is overwhelmed when the maximum capacities of the various transport mechanisms are exceeded.

Water is retrieved and urine is concentrated in a region of the kidney that is poorly perfused and highly vulnerable to the reduced blood flow that may complicate low blood pressure or inflammation.

Macroxenoglossophobe

Do you consider yourself to be an aerobic organism that is well designed to take advantage of the large amounts of energy that can be released from biological fuels such as fats and sugars by their oxidation using that vital and healthy substance, oxygen?

With what part of your cell do you associate your uniqueness?

The nuclei in your cells contain the main repository of genetic information whose carefully timed and controlled expression resulted in interactions with the environment that led to your present form and supports your temporary survival.

The nucleus retains this genetic information within a well-defined membrane - this is the defining feature of eukaryotic cells.

The cell containing this nucleus is essentially anaerobic - its cytoplasm lacks the enzymes that are required to use oxygen as the oxidising agent in the redox reactions involving glucose and other biological fuels from which useful energy is obtained. In fact oxygen is extremely poisonous to this part of the cell, causing, amongst other things, proteins to denature, fats to go rancid and nucleic acids to be damaged.

The cytoplasm of your eukaryotic cells contains large numbers of organelles called mitochondria. These have their own genetic material that is not enclosed in a well formed nucleus - the defining feature of protokaryotes such as bacteria. In fact it appears that these mitochondria are bacteria that have entered into an ancient symbiotic relationship with the eukaryotic cell. The genetic material they contain is not sufficient to make whole copies of themselves - they require some products of transcription of the eukaryotic cell's genome. It appears that they have lost genomic code that has been made redundant through access to these transcriptional products from the eukaryote's genome.

The mitochondria have the necessary enzymes to allow the use of oxygen as the oxidising agent in the redox reactions involving biological fuels from which useful energy is obtained.

Do you consider yourself to be an aerobic organism? If so you are identifying with the attenuated bacteria-like symbionts in your cells with their meagre and deficient genome rather than the eukaryotic cell with its vast repository of genetic material.

I consider myself to be an anaerobic organisms that is able to survive and prosper in an oxygen rich environment only because of an ancient symbiosis with aerobic bacteria that are themselves now genetically deficient.

If all of the eukaryotes in the world were to die tomorrow, the protokaryotes would barely notice. If all of the protokaryotes in the world (including my own symbiotic mitochondria) were to die tomorrow, the eukaryotes would die within seconds through lack of energy rich intermediate compounds derived from metabolic reactions involving oxygen.

The world belongs to protokaryotes; eukaryotes are an interesting but insignificant component of the biomass of our planet.

Why does my genome lack the necessary information to create enzymes that would allow my cells to use oxygen when it is so clearly important for my survival? Why is oxygen so poisonous to the larger part of my cells including that part which houses my genome?

scigirl

Hey Macroxenoglossophobe,

(can I call you MXG for short??),

Welcome to infidels - another medical person! Woo hoo (i'll be entering medical school soon).

Nice first couple of posts, btw.

scigirl

The Lone Ranger

Indeed, one could argue that your most important nerves don't run through the vertebral column. The 12 pairs of cranial nerves, such as the Vagus nerve, for example, don't go through the vertebral column at all. That's why if you break your neck or back, your voluntary muscles are paralyzed below that point, but your internal organs (with a few exceptions) continue to function just fine.

As important as the vertebral column is, it's a lousy place to put your main nerve cord.

Cheers,

Michael

Valentine Pontifex

I am not sure I would want to use that one. After all until recently, breaking one's back would have been lethal even if the nerves were not affected. And if one is dead, it really does not matter that one is paralyzed.

Though this would show that the "creator" was not being consistent.

Valentine Pontifex

This one would be nice if someone could find an illustration for it especially one from a work on giraffe anatomy. Of course then an illustration of how it is wired in humans would be nice as well. I think that if this one is properly illustrated with illustrations based on actual anotomy, it could be a very powerful tool.

Macroxenoglossophobe

Please do. As you probably realise, macroxenoglossophobia is a morbid fear of long strange words.
Not sure if my manipulation of html will work - please excuse me if it will not!
Thank you very much. Good luck with medical school. I think I know an electron microscopist who works in Denver. I am a fairly specialised pathologist. Let me know if you ever think I might be of help.

Oolon Colluphid

I can’t find a pic for giraffes, mostly the refs are to humans. Here’s a description of what it does: <a href="http://www.bcm.tmc.edu/oto/studs/anat/larynx.html" target="_blank">http://www.bcm.tmc.edu/oto/studs/anat/larynx.html</a>

I used to have a pic of it in an actual neck/chest dissection, but can’t find it now But between them, these three make it fairly clear:

(Annotation bottom right here):



It’s no 10 here:




It also occurs to me that, since this ‘design’ is in the blueprint of all mammals, it means that the designer used this same oddity repeatedly, in however many ‘kinds’ of mammals there are. Cats have the same perverse design as dogs, giraffes, whales, mice, civets, bats, elephants, horses, pigs, apes, and the alleged pinnacle of his efforts, humans... all of which were separate design efforts...

Cheers, Oolon

[ May 23, 2002: Message edited by: Oolon Colluphid ]</p>

Quetzal

Oolon: When are you going to figure it out? The christian deity is not a life specialist. It did really well with planets and stars - Its forte. The pixie who was supposed to make living things was sick that day so It was only subbing. An object lesson for us all on sticking with our areas of expertise...

Boro Nut

Ah, but surely giraffes are another example of poor design. Why make giraffes with long necks? The Japanese as usual have improved on the original design concept by producing much shorter trees.

Boro Nut