the.com/sphincter
the unsung valve closing your loopholes so the universe doesn't leak out of you
means A ring-shaped muscle that contracts to close a bodily passage or opening, controlling what passes through.
from From Greek 'sphinkter,' meaning 'that which binds tight,' from the verb 'sphingein,' 'to squeeze or bind' — the same root that gave us the Sphinx, the strangling riddle-monster who choked the life out of anyone who failed her quiz. So the muscle and the myth share one clenching instinct.
- count
- Humans have over 50 sphincters body-wide
- eye duty
- Pupils are controlled by sphincter muscles
- two-guard system
- Your anus has internal and external sphincters
- involuntary
- Most operate without your conscious permission
- named after
- Greek for 'that which binds tight'
lower esophageal sphincter — muscular ring preventing stomach acid from refluxing into the esophagus, fails in ~20% of adults with gerd
anal sphincter — two concentric muscles (internal and external) controlling bowel continence, studied extensively in colorectal medicine
pyloric sphincter — valve between stomach and small intestine that controls food passage, opens and closes 1-3 times per minute during digestion