How the food changes consistency and form.
The food that we eat changes consistency and form as it goes through the body’s digestive system; the digestive system is in charge of breaking down food into different nutrients that are needed for metabolic processes and getting rid of waste materials that cannot be used for further body processes.
With that being said, physical and chemical digestive processes begin right away in the mouth, when food undergoes mastication; solid food is converted into smaller pieces, and these smaller pieces are mixed with saliva, forming a semi-solid paste called bolus that is easier to swallow. The bolus moves down the esophagus to the stomach, where its churning action converts it further into smaller particle sizes. Acids and enzymes in the stomach turn the bolus into a more fluid-like substance called chyme. Chyme moves down the small and large intestines, absorbing nutrients and electrolytes. After absorption of said substances, the product would be feces, ready for expulsion from the body.
How the body was able to absorb the nutrients from the food we eat.
The nutrients from the food we eat are absorbed through the body’s major digestive organ, which is the small intestine. As the largest portion of the alimentary tube, it is also the site of nutrient absorption into the bloodstream as it has an increased surface area for food absorption. As enzymes produced by the intestinal cells and pancreas are carried to the duodenum by pancreatic ducts, and as bile (formed by the liver) enters through the bile duct, the small intestine is able to mix food with different digestive juices and enzymes in order to push for further chemical digestion. Thereafter, the walls of the small intestine absorb water and nutrients into the bloodstream.