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Kleiber - History and Hermeneutic

Posted by Gregorio on 22 Jan 2009 at 03:59 GMT

The move from the BMR of Kleiber to the FMR of Kleiber has a history steeped initially in thermodynamics. Disputation focused on the exponent of mass. Those favoring 2/3 did so on the basis of Euclidean considerations in the matter of heat lapse. Kleiber came to favor 3/4. WBE propose the fractal nature of capillary branching introduces another dimension, where metabolism concerns 'energy and materials' delivered to the cell by a variety of methods, thereby raising BMR. And, by implication, FMR, since, according to Van Savage, FMR is the product of average BMR and number of cells in the multicellular organism. WBE have always focused exclusively on vascular delivery, though they have hinted Kleiber might be relevant to neural networks. This is important.

If we are to think of the biological cell as a battery, then we must specify if this biocell is a primary or secondary cell. A primary cell is not rechargeable, and must have its waste taken away and replenished if it is to continue functioning. The biocell is traditionally considered to be a primary cell. When its voltage is recorded, the ground is located extra-cellularly. What WBE propose is a cell provided with materials and waste service provided by the blood, is capable of greater rates of energy expenditure. This form of multi-cellular organization, with its vascular delivery, is advanced by increase in mass. But mass, independently of efficiency of organizational considerations, tells us next to nothing about the relation of metabolic rate to mass. What is important is not just mass, as WBE would have it, but the structure of that mass. WBE show signs of grasping this with the fractal-delivery argument. Yet they do not introduce a variable for efficiency of that mass in their equation. Instead they assume it is 100%, and that it includes thermogenesis. This makes the WBE model biologically irrelevant. On the other hand when the variable for metabolic efficiency is introduced to Kleiber, the numbers indicate that increased mass negatively affects metabolic rate, except at efficiencies over 25%. Increased efficiency is necessary for biomass not to be penalized for increased size.

Key cellular, chemical reactions related to energy capture and transmission in the mitochondrion of the cell, are reversible, e.g., hydrolysis and synthesis of NADH and ATP. To this extent the biocell is a secondary cell. It is able to capture coulombs in the anabolism of covalent bonds. When the biocell is treated as a secondary cell while measuring cellular voltages, the ground is placed internally to the cell. The biocell has both primary and secondary aspects. The secondary aspects involve the distribution of chemical energy through hydrolysis of ATP in nerve cells, to the somatic structures and the cells that comprise them. ATP synthesis in the nerve cell is driven by digestion in the tube or gasrula of the organism. Increased encephalization translates to increased rates of secondary recharge for the organism, increasing its metabolic efficiency in the process, and thereby the FMR of the organism. The longer lives and more massive bodies of mammals awaited this increased encephalization.

But metabolic efficiency also reduces BMR. At over 25% ME all BMRs are less than FMRs. At under 25% the reverse is true. FMR is not therefore the product of average BMR and number of cells, as Van Savage et al. would have it. Longevity is directly related to MR. The ME of the organism is the same as that for its cells. This means for all creatures with an average ME of over 25%, they live longer than the cells that comprise them. The implication is that for these creatures there is a reservoir of stem cells for all somatic and nervous structures. Aging appears then to involve the antagonism between BMR and FMR. Analysis reveals far more can be deduced from this arrangement pertinent to the origins of life, its evolution, and its phases, ranging from replication to growth and development, from cancer to weight loss.

RE: Kleiber - History and Hermeneutic

Gregorio replied to Gregorio on 23 Jan 2009 at 02:30 GMT

Bertil Hille [Ion Channels of Excitable Membranes, 1991] specifies the standard techniques for measuring cell membrane voltages, and how the ground is placed extra-cellularly. This is how voltage of a primary cell is measured, where irreversible chemical corrosion in the cell gives off coulombs. The equilibrium membrane voltage for a neuron at rest, is a negative number, around -65 mV. The number changes and goes positive when the cell becomes 'excitable'. Excitability remains a poorly understood electromechanical phenomenon. Not much has changed since Hille wrote of this in a work still published as authoritative, one having endured the tests of time and new research findings.

What this clearly states is that the biocell/neuron, in its non-excited, equilibrium state, acts as a battery AT REST, and that while it discharges (sign of the voltage changes), it acts like a secondary cell, that is, one that draws from energy flow rather than one that gives off energy. This is a paradox. But one easily amended by placing the ground intra-cellularly, as if, in equilibrium, it was a secondary cell, and rechargeable; while, in the excited state, it was discharging energy like a primary cell NOT AT REST. The still poorly understood mechanism of excitability is brought into focus if bioenergy flow and nervous message traffic is thought of in terms of electrochemistry, as modeled in the sophisticated version of Kleiber's Law that includes metabolic efficiency in the exponent of biomass..