What are the three key steps of metabolism?

The three key steps of metabolism are digestion, absorption, and transport.

Digestion is the process by which food is broken down into smaller components, such as nutrients, that the body can use. This step involves both mechanical processes (like chewing) and chemical processes (like enzymatic breakdown in the stomach and intestines).

Following digestion, absorption occurs when the small molecules, like amino acids, fatty acids, and simple sugars, are taken up through the intestinal lining into the bloodstream. This is a critical step because, without absorption, the body would not be able to utilize the nutrients found in food.

Lastly, transport refers to the movement of these absorbed nutrients through the circulatory system to the cells and tissues where they are needed. This process ensures that every part of the body receives the necessary nutrients for energy, growth, and repair.

These three steps are fundamental to metabolism, as they collectively facilitate the transformation of food into energy and the building blocks for cellular functions. Understanding this sequence is essential for anyone studying nutrition and metabolism.