1.1 | Human Nervous System
1.1 | Human Nervous System
The human nervous system is an important control system for tracking and transmitting information in the body as well as coordinating body activity.
Functions of the human nervous system: - stimulation effects, transmitting information, impulse interpretations and response outcomes.
Two structures of the human nervous system: -
Central (Brain & Spinal cord)
Peripheral (Cranial nerves & Spinal nerves)
Peripheral nervous system consists of:
12 pairs of cranial nerves connecting the brain to the sensory and internal organs
31 pairs of spinal nerves connecting the spinal cord to the skeletal muscles
Brain
Spinal cord
The flow of stimulus to the response
Stimulus → Affector → Brain → Effector → Response
The types of response are divided into two: -
Voluntary Actions - conscious actions and conducted under one’s will. Controlled by the brain
Examples - writing, reading, running and talking
Involuntary Actions - occur immediately without conscious control or prior thoughts. Involving medulla oblongata & spinal cord
External control is divided into two parts:-
a) involving medulla oblongata
Heartbeat, saliva, respiratory & peristalsis
b) involving the spinal cord (reflex)
Draws hands / feet when exposed to hot or sharp objects