Question

2. Describe one of th relationship described by the equation: e hypotheses explaining the approximately 070 exponent in the weight to metabolic

Answer 1

Ans- Hypothesis explaination- The Mass, Metabolism and Length Explanation (MMLE) was advanced in 1984 to explain the relationship between metabolic rate and body mass for birds and mammals.

Most theoretical treatments of Basal Metabolic Rate (BMR) have focused on the exponent in a relationship of the form BMR = aWb where W is body mass. Two concepts have dominated. One concept is geometric similarity in which the value of the exponent b = 2/3. The theoretical explanations for this value of the exponent generally involve a balance between heat production and its loss through the body surface.

In the other concept b = 3/4. This has been known as “Kleiber’s Law”. A theoretical explanation for b = 3/4 was proposed based on a fractal network for a body’s resource supply system. More recently theoretical explanations involving resource distribution networks for which the value of the exponent b can be as small as 2/3 or as large as 3/4 have been proposed. The metabolic-level boundaries hypothesis proposes that the exponent b is proportional to the proportions of influence of volume and surface area boundary constraints and thus has a value between 2/3 and 1.0.

More microscopically, it has been proposed that an animal’s BMR is proportional to the total number of mitochondria in its tissues or to the sum of the metabolic rates of its constituent cell.

Recent analyses of BMR, body mass data have argued that there is no single exponent b that applies to a phylogenetic class such as mammals. The relationship is more complicated than BMR = aWb

It has also been argued that there are different exponents for different phylogenetic groups such as mammal orders.or different orders among insects, fish, reptiles and birds as well as mammals.

The dynamic energy budget (DEB) hypothesis an predict the absolute value of BMR rather than the exponent b in the relationship aWb.

So, we can explain as well as find out the value through this hypothesis of BMR.