Answer:
the esophageal sphincter
Explanation:
This muscle opens and lets food and liquid enter the stomach and closes to prevent the food and liquid from leaking back into the esophagus, however if it is not working properly it could open and close at the wrong times
<span>Your target heart rate h</span>as a range of two numbers.
The internet is never a good source for information, you should checkout your physician, a news article or even a pamphlet that you can acquire at your local hospital or doctors office! Maybe even checkout health seminars that are local, and possibly a book though they are often updated frequently so the information is liable to change at any point!
