Difference Between Abdomen and Stomach


Main Difference

The abdomen and stomach are two entirely different structures of human body. Abdomen is a whole region present between chest and pelvic region. Stomach is present inside the abdomen and it is the part of human digestive system. Abdomen is like a house for different organs including liver, pancreas, small and large intestine, rectum, gall bladder, spleen and stomach itself. Stomach is responsible for digestion of food that are taken by human.

What is Abdomen?

Abdomen is the region between chest and pelvic cavities. It stretches from chest at the diaphragm to the pelvis at the pelvic brim and this space is called as abdominal cavity. The boundaries of abdomen is formed by abdominal wall which includes skin, subcutaneous tissue, fascia, three layers of muscles transverse abdominis, external oblique and internal oblique, fascia transversalis and peritoneum. Abdomen is the largest body cavity which includes digestive tract, liver, gall bladder, spleen, urinary system, kidney and pancreas. In abdomen, the digestion and absorption of food occurs in the alimentary tract. The alimentary tract includes lower esophagus, stomach, small intestine, appendix, large intestine and rectum. Abdominal muscles facilitates in respiration, they assist in breathing via accessory muscles. The transverse abdominis muscle is the deepest one and cannot be felt from outside, and this muscles helps in maintaining posture. The main function of abdominal muscles is to bend the spine forward when it is coencentrically contracting.


What is Stomach?

Stomach is one of the organ present inside the abdomen. Stomach is a hollow tube like muscular organ which is an important part of our digestive system. Stomach is present between esophagus and the small intestine. Stomach aids in digestion by secreting digestive enzymes and gastric acid. Stomach is present just below the diaphragm on the left side. In anatomy, stomach is divided into four sections: cardia, body, fundus and pylorus. Stomach is connected to the lower esophagus through gastroesophageal sphincter which is responsible for keeping the food contents inside the stomach. Terminal end of stomach is connected to duodenum through pyloric sphincter. Food after digestion in stomach is then propelled into small intestine through this sphincter. Stomach can hold up to 1 liter of food because it is a distensible organ. Most of the absorption occurs in small intestine but stomach also play role in absorption of certain small molecules like; water, amino acids, water-soluble vitamins, caffeine, ethanol and aspirin. Stomach contains parietal cells which is responsible for the production of intrinsic factor that aids in the absorption of vitamin B12. Vitamin B12 is important for the production of red blood cells and maintaining the function of nervous system.


Key Differences

  1. Abdomen is the region present between chest and pelvic cavity while stomach is a organ present between the lower esophagus and duodenum.
  2. Abdomen is the part of the body that contains digestive tract, liver, gall bladder, spleen, kidney, pancreas and urinary system while stomach is part of digestive system which is present inside the abdomen.
  3. Abdomen is separated form chest by a strong muscle called diaphragm while stomach is present just below the diaphragm on the left side.
  4. Abdomen also aids in respiration and maintaining the posture while stomach aids in digestion and absorption of food.
  5. In abdomen, digestion and absorption of food occurs in alimentary tract while stomach produce digestive enzymes and gastric acid which aids in digestion.
Janet White

Janet White is a writer and blogger for Difference Wiki since 2015. She has a master's degree in science and medical journalism from Boston University. Apart from work, she enjoys exercising, reading, and spending time with her friends and family. Connect with her on Twitter @Janet__White