With the help of a diagram show the movement of food from mouth to the
stomach.What muscles and nerves are involved in the movement of food and what
is this action called ?
A .Muscles involved in movement of food from mouth to stomach :
- Typical movement of the oesophagus," stomach and intestine is called peristalsis. The muscles of the mouth enable the food to be pushed in the oral cavity.
- The first major muscle movement occurs when food or liquid is swallowed. Once the swallowing begins, it becomes involuntary and proceeds under the control of nerves in the jaw.
- Contraction and relaxation of circular and longitudinal muscles in the oesophagus bring in a wave-like motion that propels the bolus into stomach by the action called peristalsis.
- As the food approaches the closed ring of pyloric sphincter the surrounding muscles relax and allow the food to pass.
- The muscles of the upper part of the stomach have to relax and accept large volumes of swallowed material.
- The lower part of the stomach mixes food, liquid and digestive juice by its muscle action.
Nerves involved in the movement of food : - The fifth cranial nerve has been found to control the movement of muscles in the
jaw. , - Under the action of autonomous nervous system saliva is secreted to make chewing and swallowing easier.
- Peristalsis in oesophagus is also under the control of autonomous nervous system.
- When the food is in the oral cavity, the nerves in the cheek and tongue are Stimulated and carry messages in the form of nerve impulses to the brain.
- These messages are transmitted from the brain to the wall of the stomach and stimulate the gastric glands to produce gastric juice.