Explain the mechanism of the fight or flight response?

Question

Explain the mechanism of the fight or flight response?

Answer 1

In short:

When an organism feels threatened the fight or flight response kicks in. The muscles tighten, heart rate goes up, the eyes sharpen.... The organism is ready to fight or flight the threat.

Answer 2

I donnt  think newton third law of action equals opposite reaction is applicable here

Answer 3

When we experience excessive stress—whether from internal worry or external circumstance—a bodily reaction is triggered, called the "fight or flight" response. This response is hard-wired into our brains and represents a genetic wisdom designed to protect us from bodily harm. This response actually corresponds to an area of our brain called the hypothalamus, which—when stimulated—initiates a sequence of nerve cell firing and chemical release that prepares our body for running or fighting.

When our fight or flight response is activated, sequences of nerve cell firing occur and chemicals like adrenaline, noradrenaline and cortisol are released into our bloodstream. These patterns of nerve cell firing and chemical release cause our body to undergo a series of very dramatic changes. Our respiratory rate increases. Blood is shunted away from our digestive tract and directed into our muscles and limbs, which require extra energy and fuel for running and fighting. Our pupils dilate. Our awareness intensifies. Our sight sharpens. Our impulses quicken. Our perception of pain diminishes. Our immune system mobilizes with increased activation. We become prepared—physically and psychologically—for fight or flight.

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