1. How the food changes consistency and form?
Our mouth is where the digestive system begins through a mechanical and chemical process. First, mastication, often known as mechanically shearing large portions of food into smaller ones, is the process of chewing food. Once saliva is added, it combines to form a bolus, a semi-solid mixture that is simple to swallow. By acting on the starch, salivary amylase labels the chemical digestion of meals. Water is used to hydrate and dissolve the meal. The mucus helps with swallowing by lubricating the food. Once in the stomach, the churning movement continuously mechanically cuts the bolus into an even smaller particle size. The food then passes via the esophagus on its way there. The acid and digestive enzymes released in the stomach chemically alter the meal by breaking down complex molecules into simpler versions. The bolus must be transformed throughout this process into a fluid-like substance called chyme. Chyme descends and heads for the small intestine. The duodenum, which is the site of primary chemical digestion, is the host of enzymes operating on chyme. While the segmentation process causes physical digestion. Over time, food releases its nutrients in the form of glucose (from sugars), fatty acids and glycerols (from lipids and fats), amino acids (from proteins), and nucleic acids (from nucleoproteins). Additionally, vitamins and electrolytes are available for free absorption in the small intestine. The absorption is helped by the ongoing backlash movements along the intestinal lumen's microvilli. Through the absorption of the nutrients, they will be released from the food. Finally, it will experience defecation, in which wastes, including germs, indigestible compounds, waste products, and cells shed from the GI tract's lining, exit the body through the anus and the eliminated material, feces.
2. How the body was able to absorb the nutrients from the foods we eat?
The entire mechanical and chemical stages of digestion from the Food is transformed into forms that can pass past the absorptive epithelium cells lining the mucosa and into the underlying blood and lymphatic vessels from the mouth through the small intestine. These include single amino acids, dipeptides, and tripeptides from proteins; monoglycerides, glycerol, and fatty acids from triglycerides; and monosaccharides (glucose, fructose, and galactose) from carbohydrates. Absorption is the process through which these broken-down nutrients move from the gastrointestinal tract into the blood or lymph. Diffusion, assisted diffusion, osmosis, and active transport are all methods of material absorption. Anything that is still in the small intestine after being digested or absorbed moves on to the big intestine.
References:
Tortora, G. J., & Derrickson, B. (2014). Principles of Anatomy and Physiology (14th ed.). Wiley.
Bartelby. (n.d.). The Digestive System. Retrieved from https://www.bartleby.com/solution-answer/chapter-23-problem-1ilq-anatomy-and-physiology-1st-edition/9781938168130/by-clicking-on-this-link-httpopenstaxcollegeorglfooddigestion-you-can-watch-a-short-video/cad5bd3e-0e4c-11e9-9bb5-0ece094302b6