sphincter muscle
Học thuậtThân thiện
The sphincter muscle at the base of the esophagus relaxes to allow food to pass into the stomach.
Definition
- Noun:
- A ring of muscle that contracts to close an opening: A sphincter muscle is a circular band of muscle fibers that surrounds a natural opening or passage in the body. Its primary function is to constrict or close that opening by contracting.
Usage
- The term "sphincter muscle" is used in anatomical and medical contexts to describe specific muscles that control the flow of substances by opening and closing bodily orifices.
- It is typically modified by the name of the specific orifice it controls (e.g., anal sphincter, pyloric sphincter).
Examples
- Noun:
- The anal sphincter muscle helps maintain continence.
- Damage to the esophageal sphincter muscle can cause acid reflux.
Advanced Usage
- Physiological Role: Sphincter muscles are often discussed in terms of their tonic (constant) or phasic (periodic) contraction patterns.
- The internal anal sphincter provides tonic contraction to maintain closure at rest.
Variants and Related Words
- Sphincter (n): The more common, abbreviated term for "sphincter muscle."
- The pyloric sphincter regulates the passage of food from the stomach.
- Sphincteric (adj): Relating to or having the characteristics of a sphincter.
- The patient exhibited impaired sphincteric control.
Synonyms
- Constrictor muscle: A muscle that narrows a passage or compresses an organ.
- Circular muscle: A general term for muscles arranged in a ring-like fashion.
Related Phrases
- Sphincter of Oddi: A specific sphincter muscle controlling the flow of bile and pancreatic juice.
- Dysfunction of the Sphincter of Oddi can cause severe abdominal pain.
- Sphincterotomy: A surgical procedure to cut a sphincter muscle.
- The surgeon performed a sphincterotomy to relieve the obstruction.
The sphincter muscle at the base of the esophagus relaxes to allow food to pass into the stomach.
Noun
- a ring of muscle that contracts to close an opening