Question

Define reflex action. With the help of a flow chart show the path of a reflex action such as sneezing.

Answer 1

A reflex action is an automatic, involuntary reaction to a stimulus that bypasses conscious brain processing. These actions serve to safeguard the body from injury and facilitate swift reactions. For instance, sneezing serves to clear irritants from the nasal passages.
Key Attributes of Reflex Actions:
• They are instantaneous and automatic.
• They possess a protective function.
• They circumvent the brain, engaging solely the spinal cord and nerves.
Process Diagram:

Illustrative Case: The Sneezing Reflex: Upon the entry of an irritant, such as dust or pollen, into the nasal cavity, sensory neurons detect the irritant and transmit a signal to the spinal cord. Motor neurons then stimulate the diaphragm muscles, resulting in a sudden, powerful expulsion of air that eliminates the irritant.