Asked by: Sophie Footitt, by email
Probably to grab a little extra oxygen. Gasping is part of the flight/fight response in which adrenalin and other hormones are released to prepare the body for action. These dilate pupils, speed up heart rate, breathing and metabolic rate, and supply more fuel to the muscles. All these changes mean using oxygen more quickly, so a good deep gasp might be a useful precaution.
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