Write down three important charateristics of a reflex action.

Explanation

### Step-by-Step Solution:

1. **Involuntary Response**: Reflex actions are involuntary responses, meaning they occur automatically without conscious thought. This characteristic allows the body to react quickly to harmful stimuli, ensuring safety and protection. For example, when a child touches a flame, they instinctively pull their hand back without thinking about it.

2. **Sudden Reaction**: Reflex actions are sudden and immediate. They happen in response to a stimulus almost instantaneously. This quick reaction is crucial for survival, as it minimizes the time the body is exposed to potential harm.

3. **Neural Pathway Involvement**: Reflex actions involve a specific neural pathway known as the reflex arc. This pathway includes sensory neurons that detect the stimulus, a central relay site (the spinal cord), and motor neurons that execute the response. The process involves sensory inflow (detection of the stimulus), a central relay (processing of the signal), and motor outflow (the action taken in response).

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