Absorption

• Absorption is the movement of nutrients from the intestines into the blood, so they can be transported to different parts of the body.

Imagine the small intestine as a gateway to the bloodstream. After the nutrients are broken down during digestion, they pass through the walls of the small intestine like travelers passing through customs at an airport. Once cleared, these nutrients enter the bloodstream and travel to different organs and tissues in the body.

Assimilation

• Assimilation is the uptake and use of nutrients by cells for energy, growth, and repair.

Think of assimilation as the delivery of packages to different parts of your body. Just as a delivery person brings packages to your home, the bloodstream delivers nutrients to cells, providing them with energy and the building blocks they need for growth and repair.

Small Intestine – Duodenum and Ileum

The small intestine is the primary site of nutrient absorption. It receives chyme from the stomach and further breaks down food using enzymes produced by the pancreas and intestinal wall. Nutrients are then absorbed into the bloodstream.

Imagine the small intestine as a conveyor belt in a factory. As the chyme moves through the small intestine, nutrients are absorbed from it and delivered into the bloodstream, just like products being sorted and transported along a conveyor belt in a factory.

Egestion

• Egestion is the removal of undigested food from the body as feces.

Imagine the large intestine as a waste disposal system. After the nutrients have been absorbed, the indigestible and unused parts of the food, along with some water, form feces. The large intestine acts like a garbage collector, gathering the waste and storing it until it’s ready to be eliminated from the body through the rectum and anus.

Large Intestine – Colon, Rectum and Anus

The large intestine absorbs water and electrolytes from the remaining undigested food, forming feces. It stores feces until elimination through the rectum and anus.

Think of the large intestine as a sponge that absorbs excess water from the undigested food, leaving behind a more solid mass, similar to how a sponge soaks up water from a surface.

Associated Organs

Salivary Glands

Salivary glands secrete saliva into the mouth, containing enzymes like amylase that start breaking down carbohydrates.

Imagine the salivary glands as factories that produce a special liquid (saliva) containing enzymes like amylase. When you start eating food, these factories become active and release the liquid to help break down the carbohydrates in the food.

Pancreas

The pancreas is a gland that produces digestive enzymes and releases them into the small intestine to further break down proteins, fats, and carbohydrates.

Think of the pancreas as a chef in the kitchen. Just like a skilled chef adds different spices and flavors to a dish to enhance its taste, the pancreas releases various digestive enzymes into the small intestine to further break down the food and make it easier to absorb nutrients.