PHYL2001 Lecture Notes - Lecture 2: Autonomic Nervous System, Somatic Nervous System, Skeletal Muscle
Document Summary
Homeostasis maintenance of a relatively stable internal environment: e. g. temperature, [o2], ph, levels of nutrients, waste products & electrolytes body systems maintain within the narrow confines of the life. In the control of body systems : sensor-> sensory nerves/cells, effector processes activated. Integrator brain by efferent nerves and hormone systems. The afferent (towards the cns) nervous system consists of the: sensory nerves. Somatic nervous system: neurological system that allows the individual to respond voluntarily to consciously perceived sensory signals, the somatic ns response consists largely of responses giving rise to voluntary skeletal muscle contraction. It"s a 2 neuron chain: pharmaceuticals target these synapses to turn the signals on or off. One preganglionic neuron can synapse onto many postganglionic neurons: the sensory neuron can activate all post-synaptic neurons, but all will do different things, either turn on or off, hence more fine-tuned and coordinated response control. Single preganglionic neuron can synapse onto both excitory and inhibitory postganglionic neurons.
