Page 44 - Consciousness in the Cell

CONSCIOUSNESS IN THE CELL

YOU ARE NEVER IN CONTROL OF YOUR

BREATH, BECAUSE SOME OF YOUR CELLS

CONTROL IT FOR YOU

If regulation of our breathing were left up to us we would
probably die of asphyxiation from forgetting to breathe, falling
asleep or being preoccupied with other activities.
For every human being, this crucial process is regulated by the
respiratory center, which is the size of a lentil bean and is located
in the brain stem (an extension of the brain). It is made up of three
different groups of neurons.
The first group determines the basic rhythm of breathing and
gives the lungs and the chest the signal to inhale air. In this way,
we breathe in the air we need.
The second group of cells determines the speed and pattern of
our breathing. When this second group comes into play, however,
the cells signal to the first group to halt their activity. This controls
the air capacity of our lungs, and our breathing speeds up.
The third group, on the other hand, is not normally active.
They come into play when a high rate of breathing is needed and
they ensure that the abdominal muscles participate by sending
them signals.
Is all of this enough to keep us alive? No.
Respiration is also controlled chemically. Breathing's aim is to
maintain the correct balance of oxygen and carbon dioxide in our
blood. Any change in this balance activates a group of cells in the
respiratory center, bringing the levels back to normal with very
sensitive adjustments.
But the amount of oxygen in the blood has no direct effect on
the respiratory center. In that case, how does the respiratory cen-
ter become aware of the change in oxygen level in the blood?

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