Acid reflux into the esophagus ("heartburn") is normally prevented by ________.
A. pharyngeal and buccal sphincters
B. the lower esophageal sphincter (LES)
C. pharyngeal constrictors
D. esophageal glands
E. the upper esophageal sphincter
Answer: B
You might also like to view...
Which of the following is a degenerative joint disease in which joint cartilage is gradually lost due to a combination of aging, obesity, wear and abrasion of the joints?
a) gouty arthritis b) Lyme disease c) bursitis d) osteoarthritis e) synovitis
Tom gets a cut on his hand. After several days he notes swelling, pain, heat, and redness. Upon opening the wound to relieve the pressure, the presence of pus is noted. What has happened to the wound?
What will be an ideal response
The hilum of the spleen is part of its
A. convex posterolateral border. B. convex anteromedial border. C. concave anteromedial border. D. concave posterolateral border.
The thymus gland secretes erythropoietin in response to low blood oxygen.
Answer the following statement true (T) or false (F)