What is the process of digestion in man?

How do things get broken down during the digestive process?

• A man eats a cheese burger with the following ingredients: bun, beef patty, mustard, American cheese, pickles, lettuce, tomatoes, and avocado. It is then followed by baked sweet potato fries, a glass of whole milk, and a red delicious apple. Can you please help me take this meal and move it through the human digestion system. And explain where each item is broken down by physical or chemical digestion and the process of movement of materials, the enzymes used to break down the materials, and where each nutrient would be absorbed?

• Answer:

  You are asking for a journal detailing each hormonal and enzymatic process in digestion, and that is simply not going to happen here. Digestion involves more than the digestive system (the nervous, endocrine, and circulatory systems are heavily involved, too). Suffice it to say that actual digestion involves the mouth (reducing the size of the ingested material), saliva (amylases in it help begin reducing carbohydrates and proteins to their respective sugar and amino acid constituents), and the stomach. The intestines only involve elimination (peristalsis) and nutrient absorption.