The Digestion and Absorption Journey of an Omelette

Author: Zhang Yujian, Song Xuenan, Gong Liying, Qilu Hospital of Shandong University

Reviewer: Ji Rui, Chief Physician, Qilu Hospital, Shandong University

The first ray of sunlight in the morning shines through the curtains and falls on the face of the little girl Yueyue.

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"Come and have breakfast!" Mom's voice came from the dining room. Yueyue rubbed her sleepy eyes, climbed out of bed, and ran to the dining room impatiently. A delicious breakfast was placed on the table: golden fried eggs, crispy toast, and a cup of steaming milk. The girl excitedly picked up a fork, picked up a piece of golden fried egg, and put it in her mouth. "Hmm, it smells so good!" Yueyue squinted her eyes and chewed the delicious breakfast. Little did she know that this small fried egg was about to start a magical adventure.

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The journey of the fried egg begins in Yueyue's mouth. The first thing that comes into her mouth is the taste experience. The taste buds perceive the sweet, sour, bitter, salty, and fresh tastes of food, and transmit information to the brain, triggering appetite and saliva secretion. With a light bite, the fried egg is cut into pieces by her teeth and mixed with her saliva.

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Saliva contains a special enzyme that can initially break down the protein in the fried egg, making it easier to digest.

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Then, the fried egg fragments are pushed by the tongue and slide down the esophagus. The esophagus is like a slide, sending the fried egg to the stomach. Once in the stomach, the fried egg's journey becomes even more amazing. The stomach wall muscles begin to contract violently, and the fried egg feels as if it has been sent into a blender, which thoroughly mixes the fried egg with gastric juice.

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Gastric juice contains strong acidic substances, which can further break down the protein in the fried egg and turn it into smaller molecules. The fried egg stays in the stomach for about two hours, and it is broken down into smaller particles by the gastric juice and enters the small intestine together with the gastric juice.

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The small intestine is like a winding river, up to 6 meters long. Here, the journey of frying eggs really enters the busy stage. With the participation of bile, pancreatic juice and various biological enzymes, the protein, fat and carbohydrates in the frying eggs are completely broken down and absorbed by the human body.

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The decomposed nutrients are absorbed by the villi of the small intestine, which are like tiny hairs that can transport nutrients into the blood. The blood is like a high-speed train that transports these nutrients throughout the body, providing energy for various organs and helping them work normally.

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Finally, the fried egg reaches its destination: the large intestine. The large intestine is like a garbage disposal plant, absorbing indigestible residues and water into feces and excreting them from the body.

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After the journey, the girl felt full of energy and went to school. She didn't know that while she was enjoying her delicious breakfast, the fried egg had completed its magical journey in her body and provided energy for her growth.