How strong is our stomach acid?

Biology / 7 min read / 27 January 2022

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Lazy Science Reader,

The journey of food does not end after it is done being cooked. Infact, that’s barely the half of it. It’s true journey begins when it enters our body. With many stops, it gets ingested, digested, absorbed, assimilated and then egested. One of the most vital tracts in our body is the digestive tract. Food which goes from the buccal cavity to the anus goes through a tract called the alimentary canal. The alimentary canal along with the digestive glands from the digestive system.

Which organs are present in it? The buccal cavity, which consists of the tongue, teeth and the salivary glands, the esophagus which contracts and relaxes to push food down (peristalsis), stomach, liver, pancreas, small intestine and the large intestine, rectum and anus.

However today, the organ in the spotlight is the stomach. The role of stomach in the process of digestion is very important. When food enters the stomach, it expands and the gastric glands present in the wall of the stomach release gastric juices containing HCl, NaCl, KCl. Our stomach also secrets enzyme pepsin and mucus. HCl kills the bacteria, enzyme pepsin converts complex substances (proteins) into simpler substances (peptons). There are several other such enzymes present in organs of the digestive system which are responsible for this breakdown of complex substances eg, enzyme amylase helps in breakdown of starch. Lastly, mucus helps in protection of stomach walls.

How strong is the stomach acid? We know from the above paragraph that gastric juice, or stomach acid is composed of potassium chloride, sodium chloride and hydrochloric acid. Due to the presence of these, the pH value of stomach acid ranges from 1 to 3. This somewhat brings stomach acid within the range of battery acids that dissolve steel. So, if the stomach acid is so strong, why don’t we have a hole in our stomach? That’s because of the secretion of mucus by our epithelial cells. Along with that, the coat of the stomach in contact with the food is that of bicarbonate. The bicarbonate neutralizes the stomach acid therefore protecting our stomach while the mucus acts as a barrier.

However, just because there’s a possibility that our stomach is capable of dissolving steel, objects such as pennies can be fatal. The thing about coins minted since 1982 is that they are made up of zinc with a coat of copper. Our stomach acid is capable of dissolving copper but the zinc can cause a lot of problems such as bleeding ulcers, vomiting etc.

That’s all about stomach acid for today. Stay in tune for more articles!


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