BIOL 241 Chapter Notes - Chapter 35: Walter Bradford Cannon, Autonomic Nervous System, Neuron
8 Jul 2017
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The autonomic nervous system plays a key role in the ability to maintain homeostasis, or a steady physiological state, in the face of changing environmental conditions. Selectively permeable cell membrane helps maintain homeostasis within individual cells. For example, it keeps ion concentrations within narrow ranges for normal cell function. Similarly, the ring of action potentials by neurons requires particular ion concentrations on either side of the membrane. Temperature and ph are other parameters that do not vary much because enzymes often work effectively only in narrow temperature and ph ranges. Recent evidence suggests that nerve cell ring rates are maintained at a steady level in the brain of rats, regardless of sensory stimulus or deprivation, or whether the animals are awake or asleep. A shift in the homeostatic set point of nerve cell ring rates may therefore underlie disorders of low brain activity, such as autism. Homeostasis is also maintained for the whole body.
