How Undigested Food Changes In The Digestive System

Just recently, a parent in our Parent Support Group asked us for help on a question on the amount of undigested food in the different organs of the digestive system.

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As such, in today’s article, I’ll be sharing on the process of digestion and what the amount of undigested food at the end of each organ is.

Question:

Explanation

Part A – Mouth – Digestion starts here

• Food first enters the mouth where it is broken down into smaller pieces and acted on by the saliva.
• The amount of digested food increases, while the amount of undigested food DECREASES when the food is leaving the mouth (A).

Part B – Gullet– No digestion occurs here

• The gullet contains muscles to push the food down to the stomach.
• The amount of digested food remains the same and the amount of undigested food REMAINS THE SAME.

Part C – Stomach – Digestion continues to occur here

• The stomach acts like a washing machine to churn and mix the undigested food with the stomach’s digestive juices for the food to be digested.
• The food stays in the stomach for a couple of hours before it is released into the small intestine.
• The amount of digested food increases and the amount of undigested food DECREASES.

Part D – Small Intestine – Digestion continues to occur and ends here

• The small intestine has the largest amount of digestive juices and will most of the digestion of food is carried out here.
• After the food that can be broken down has been digested, the digested food is then absorbed into the bloodstream through the walls of the small intestine.
• The amount of digested food increases and the amount of undigested food DECREASES.

Hence, the answer for this MCQ is Option 2.

I hope that this article has helped to introduce the functions of the different parts of the digestive system and clarify where digestion takes place in the system!