-
How the food changes consistency and form
The moment the food enters our mouth starts the change in its consistency and form. Our digestive system breaks down food through two methods known as mechanical digestion and chemical digestion. Mechanical digestion is wherein food is broken down because of the chewing, churning, propelling, and peristalsis. This type of digestion involves involuntary contractions and relaxations of muscles in the digestive system. Chemical digestion, on the other hand, is the secretion of enzymes that breaks the food particles chemically into smaller parts that can be digested by the body. Our digestive system consists of six processes:
-
Ingestion is the process by which we intake food and liquids through the mouth.
-
Secretion of needed water, acid, buffers, and enzymes needed by digestive processes.
-
Mixing and propulsion that involves contractions and relaxations of muscles in the GI tract that provides motility to the broken down material in the tract.
-
Digestion, mechanical and chemical, is the process that breaks down the ingested food into smaller molecules. Food molecules from mechanical digestion then gets mixed with enzymes and so the chemical digestion proceeds where hydrolysis occurs.
-
Absorption of the nutrients from the broken down food molecules. Absorbed substances and nutrients go into the blood or lymph and circulate throughout the body.
-
Defecation is the process where substances that are not digested, also known as wastes leave the body. The eliminated waste is called feces.
-
How the body was able to absorb the nutrients from the foods we eat.
Ingested food is broken down into smaller particles into smaller molecules. These forms are monosaccharides from carbohydrates, amino acids, dipeptides, and tripeptides from proteins, fatty acids, glycerol, and monoglycerides from triglycerides. Absorption of these materials occurs through diffusion, osmosis, and active transport. Digested nutrients are transported into the blood and lymph and circulate throughout the body. Unabsorbed material will then go through the large intestine.
References
Tortora, G. J., & Derrickson, B. H. (2018). Principles of anatomy and physiology. John Wiley & Sons.