How do reflex arcs work?
Answer
Ouch! You see how fast the hand was removed from a hot stove? Our bodies have a system in place that enables us to act really quickly, which is called reflex reactions. Reflex reactions are immediate, unconscious responses to a stimulus. Reflex reactions provide us with protection and facilitate our survival. Remember the nervous system and it's pathway? A stimulus hits a receptor and that impulse travels through the sensory neuron to the CNS (brain)/ The CNS (brain) then transports the response to a motor neuron which then elicits an effector response. Sensory neurons, motor neurons, and relay neurons differ from one another.
Touch a boiling plate, face to face with a lion, or an eye reacting to light you want a fast reaction to all. When your safety demands a quick response, the signal may bypass the brain and be acted upon as soon as it reaches the spinal cord. These shorter pathways are called reflex arcs. Reflex arcs are built in for innate behaviors, and we all behave the same way. In reflex arcs, a stimulus hits a receptor and that impulse travels to the spinal cord immediately telling the somatic nervous system to move that muscle without even a single input from the brain. Even though the brain is bypassed for the immediate response, the nerve message is still passed on to the brain using a different route. The brain then thinks about if there are any further actions that are needed to be done.
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