Explanation:
Why is it beneficial for an organism to have its tissues near its optimal temperature? List various functions or activities that may be affected if the body temperature deviates too far from the temperature optimum (which functions or activities are mediated by proteins)?
a.) Muscle-movements
b.) Digestion of food
c.) Growth and development
Just about every aspect of an organisms daily functions are governed by the actions of proteins, be they structural proteins that determine cell shape, motor-protein that move vesicles inside the cell or allow muscle cells to contract, or be they enzymes that catalyze the vast majority of chemical reactions a cell has to engage in.
It turns out that every living organism gives off some heat. The difference between endotherms and ectotherms is merely the rate at which this heat is produced by the organism.
In fact, even plants and bacteria produce some heat as they go through their daily lives. This is evident in early spring, when the earliest spring flowers manage to thaw themselves through a solid ice layer, or when you overturn a compost heap on a crisp fall day in which bacteria decomposers are very active you will see steam rising from the pile.
What source have we already discussed that can produce this heat given off by organisms to their environment?
a) negative delta G of energetically coupled reactions.
Endotherms take advantage in particular of cellular respiration to ramp up that heat given off from energetically coupled reactions due to the Second Law of Thermodynamics.
As a consequence, endotherms maintain highly elevated rates of cellular respiration compared to ectotherms
b.) lowering of activation energy by an organism's enzymes
