Nervous system:
1. CNS
2. PNS
CNS
- consist of brain + spinal cord
PNS
- consist of nerves outside the brain and spinal cord
- cranial nerve (12 pairs) - emerging from the brain - mainly supply structure above the neck
- spinal nerve (31 pairs) - emerging from the brain - supply structures in the trunk + limb
Note: Neuron
- afferent (sensory) = carry impulses towards CNS
- efferent (motor) = carry impulse away from CNS
- interneuron = reside entirely within CNS
Efferent nerve - 2 types
(a) Somatic nerve (motor nerve) - innervate skeletal muscle(somatic nervous system)
(b) Autonomic nerve (motor nerve) - innervate cardiac muscle, smooth muscle or glands (Autonomic Nervous System - ANS)
Action carried out by somatic nervous system are voluntary.
Action carried out by ANS are involuntary + automatic
Sensory Neuron
Carry impulse into CNS from receptors.
Receptors
- for general senses (touch, pressure, vibration, temperature, pain + proprioceptor)
- for special senses ( smell, taste, vision, hearing + equilibrium)
Buku Politik Perlis
8 years ago
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