How do hormone responses occur so rapidly? When people are frightened/surprised, they can almost immediately feel a rush of adrenaline and heart rates rise, faces flush, etc. How do hormones reach appropriate organs so quickly? Why isn’t there more of a delay for the hormones to travel?
In: Biology
Actually just learned this last semester!
The ELI5 version is that the hormone “adrenaline” flows through your bloodstream (endocrine system) and attaches to receptors on the cells of your heart muscles (could be wrong on the exact location) and causes a change in the cells and tells your heart to beat faster, which is why you feel more flush and why sometimes you can feel your heart beating through your chest.
The endocrine system is surprisingly fast, and rightfully so, because if you’re in a life or death situation you need that adrenaline NOW. That’s why it’s called the “fight or flight” response, sometimes.
A more in depth way of explaining why they happen so fast also has to do with the amount of change that occurs in the cell due to a cascading event starting from one molecule, which turns on a bunch of other proteins, and so on and so forth until one molecule essentially turns on dozens or hundreds of other molecules responsible during the adrenaline response.
Some of my thoughts could be wrong, someone will have to correct me as i am pulling from memory and on mobile.
Edit: “feeling” to “response”
Edit: Some others have added some additional, useful details. Credit where credit is due:
u/OwariNeko
u/barelystanding
u/theherbiwhore
u/KrauMing
had some ELI5 and some non-ELI5 responses that add information I left out or did not know. Thanks!
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