Consuming food is an everyday thing we all do. But what happens after swallowing it?
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Digestion:the breakdown of nutrients so that they can be used by the body’s cells. Many organs contribute to the process of digestion, and in this article, you are going to read about the humans’ digestive system.
An overview of digestion
The mouth is the place where digestion starts. Saliva secreted by the salivary gland moistens the food so that it’s easier to swallow; at the same time, a type of enzyme called amylase breaks down the carbohydrates in the food.
The food then moves from the mouth to the esophagus, where food continues to be passed down to the next step of digestion.
The stomach receives food from the esophagus, and it secretes acid and enzymes (hydrochloric acid and pepsin) that break the food down.
Then, the food is transported into the small intestine, where nutrients are absorbed into the bloodstream.
Finally, in the large intestine, water and vitamin K are absorbed, and the unabsorbed leftovers would be stored in the rectum and eliminated through bowel movements.
Peristalsis
To move food through the GI tract (tube where food passes), a process called peristalsis is extremely important. Peristalsis is when the smooth muscles of the organs of the GI tract, or the muscles of the internal organs of the GI tract contract, and therefore push the food or liquid through the GI tract. This is also why even if it when we are doing a handstand, our digestive system can still work regularly.
Accessory Structures
Beside the organs mentioned above that contribute to digestion, the accessory structures, including the liver, gallbladder, and the pancreas, are where food does not actually pass through. Instead, they assist in the process of digestion. The liver produces bile, which is used to break down fats; the gallbladder stores bile; and the pancreas secretes other enzymes like lipase, protease, and amylase. Once the food enters the small intestine, the secretions of the accessory structures would join and help with the process of digestion.
Finally, what is the significance of digestion?
Digestion is extremely important for us because it breaks down the nutrients and therefore provides us energy, and helps with growth and cell repair.
Because of digestion, our body can perform vital functions, and we can stay healthy.
Written by: Benetta Wang
Reference:
“Your Digestive System & How It Works.” National Institute of Diabetes and Digestive and Kidney Diseases, 21 Aug. 2020, www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works.
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