Structural and Functional Divisions of Nervous System
PNS Divisions
Sensory (afferent) division Somatic sensory fibers: convey impulses from skin, skeletal muscles, and joints to CNS Visceral sensory fibers: convey impulses from visceral organs to CNS - Motor (efferent) division Transmits impulses from CNS to effector organs - Muscles and glands Two divisions - Somatic nervous system - Autonomic nervous system
Autonomic Nervous System
- Consists of visceral motor nerve fibers - Regulates smooth muscle, cardiac muscle, and glands - Involuntary nervous system - Two functional subdivisions Sympathetic-Your sympathetic nervous system is a network of nerves that helps your body activate its "fight-or-flight" response. This system's activity increases when you're stressed, in danger or physically active. Parasympathetic-Your parasympathetic nervous system is a network of nerves that relaxes your body after periods of stress or danger. It also helps run life-sustaining processes, like digestion, during times when you feel safe and relaxed Work in opposition to each other
Somatic Nervous System
- Somatic motor nerve fibers conduct impulses from CNS to skeletal muscle - Voluntary nervous system Conscious control of skeletal muscles
Central Nervous System (CNS)
Brain and spinal cord of dorsal body cavity Integration and control center - Interprets sensory input and dictates motor output
Peripheral Nervous System (PNS)
The portion of nervous system outside CNS Consists mainly of nerves that extend from brain and spinal cord - Spinal nerves to and from spinal cord - Cranial nerves to and from brain
