Science
Define reflex action. With the help of a flow chart show the path of a reflex action such as sneezing.
Nervous System
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Answer
A reflex action is an automatic, quick and involuntary response to a stimulus that does not involve the conscious part of the brain. It helps in protecting the body from harm and occurs through a pathway called the reflex arc.
Example – Reflex action in sneezing :
When dust or an irritant enters the nose, sensory nerves detect it and send signals that cause the muscles of the chest and diaphragm to contract suddenly, forcing air out — this is sneezing, which expels the irritant.
Flow chart showing the path of reflex action (Reflex Arc):
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