There are many, many complex functions of the body at a cellular level, at the level of tissues and organs, and then as an integrated whole in carrying out actions based on willful choices and desires. All of this activity needs to be carefully orchestrated and coordinated to work smoothly so that the available energy is marshaled and put to use in a way that is efficient, productive, and stays within a reasonable limit to not create excesses that can cause problems such as excessive wear and tear, or the exhausting of vital resources that could be dangerous if made unavailable to other essential bodily functions, and so on. All must work in harmony and all must be in balance, each playing its assigned role, and each being called to greater duty on demand when this is appropriate and required, when there is a conscious choice to do something that calls for greater energy and then all that must be marshaled to provide it. Everything from the ingestion of food, the intake of the breath, the excretory functions, and all that happens in between with digestion, with assimilation, the metabolic functions to transmute and transfer nutritional elements to create the building blocks for cellular function, and the interplay of communication electrically and chemically within the tissues as well as the bioenergy fields themselves receiving support and energy from the environment—all is under regulation and oversight by consciousness.
This is too vast a job, and too detailed, and too minute in terms of scale as most of this goes on within truly microscopic cellular elements that are unable to be visualized directly let alone understood in their detailed workings. This is why much of the regulation and oversight must be done on a subconscious level, and even a cellular level, with respect to sensing and reacting, with many decisions along the way based on the template for life to keep things humming along within normal limits and understanding, and taking action when things drift from the center line, so to speak, and adjustments are called for. This is a requisite for healthy function and for life to continue to exist and is the final onset of death when the oversight can no longer be provided, and then everything goes into disarray or closes down in stages as the instructions cease and the flow of energy will not permit additional function to take place. This cannot be done through conscious awareness whatsoever, so the body-mind carries most of the burden for maintaining life and even carrying out life as desired by the conscious self.