Apr 09 2008
Digestion
Digestion is the process in which the body breaks down food into smaller components that can be absorbed into the blood stream. In mammals, preparation for digestion begins with the cephalic phase when saliva is produced in the mouth and digestive enzymes are produced in the stomach. Mechanical and chemical digestion begin in the mouth where food is chewed and mixed with saliva to break down starches. The stomach continues to break down food mechanically and chemically through the churning of the stomach mixing with enzymes. Absorption occurs in the stomach and gastrointestinal tract, which finishes with excretion. Levels of pH play an important role in proper digestion.
The 4 seperate stages of digestions include:
1-Ingestion: placing food into the mouth
2-Mechanical and Chemical Digestion: mastication to tear and crush the food, and churning of the stomach. Addition of chemicals such as bile, acid, enzymes and water to break down complex molecules into simple structures
3-Absorption: moving the nutrients from the digestive system to the circulatory and lymphatic capillaries through osmosis, active transport and diffusion
4-Egestion: removal of undigested materials from the digestive tract through defecation
Digestion is a pretty complicated process, think of how amazing our bodies are to be able to break down all the different foods we eat on a daily basis!! The human body is incredible! Have a good week everyone!! Enjoy the beautiful weather!
