Everyone would die and the human population would eventually die out.
I believe the answer to your question is external stimuli
I'm not sure of your question, but I think you're looking for <span>esophageal sphincter. </span>
Hard hat: protects the head from falling objects
Leather gloves: protects hands from cuts and debris
Goggles: protects eyes from dust and air borne debris
N-95 respirator mask: prevents from breathing in dust, hazardous gases
Yellow vest: allows others to recognize that you are a responder and not a victim
