Human Digestive System
Human Digestive System
The digestive tract is a series of hollow organs through which food passes: mouth, pharynx, esophagus, stomach, small intestine. Each portion is specialized for one or more aspect of the three major functions of the digestive system the secretion, digestion, and absorption. Accessory organs such as salivary glands, liver, gallbladder and pancreas have duct that lead into the digestive tract and thus support digestive function. Digestion is defined as the mechanical and chemical breaking down of food into smaller components, to a form that can be absorbed and utilized by the cells of the body. The two phase of digestion are mechanical and chemical or enzymatic. The former involves the movement of organs while the latter involvesthe actions of enzymes in the process of digestion. These enzymes produced by the body cell and released catalyze specific chemical reaction.
Mouth
Mouth the beginning of the one-way human digestive tract. Mouth does not only serve as the entrance of food but is also functioning in digestive process. It features teeth and tongue that are both accessory organs of digestion as well as saliva. The teeth are responsible for tearing, biting and churning of food. Tongue is responsible for determining taste of the food, mixing them and pulling bolus down the esophagus in the process of swallowing or deglutition. The salivary glands release saliva that lubricates the food for easy swallowing and pass to esophagus and it contains the salivary amylase that is responsible for breakdown of carbohydrates. Saliva is a watery solution containing mucus, mineral ions and digestive enzymes. The enzyme is secreted by the salivary glands are parotid glands, submandibular glands and sublingual glands. Parotid glands are secretes a serous solution that flows through a parotid duct leading to the cheek wall across from the second upper molar. Submandibular glands are produce mostly serous fluid and mucous fluid. Sublingual
The digestive tract is a series of hollow organs through which food passes: mouth, pharynx, esophagus, stomach, small intestine. Each portion is specialized for one or more aspect of the three major functions of the digestive system the secretion, digestion, and absorption. Accessory organs such as salivary glands, liver, gallbladder and pancreas have duct that lead into the digestive tract and thus support digestive function. Digestion is defined as the mechanical and chemical breaking down of food into smaller components, to a form that can be absorbed and utilized by the cells of the body. The two phase of digestion are mechanical and chemical or enzymatic. The former involves the movement of organs while the latter involvesthe actions of enzymes in the process of digestion. These enzymes produced by the body cell and released catalyze specific chemical reaction.
Mouth
Mouth the beginning of the one-way human digestive tract. Mouth does not only serve as the entrance of food but is also functioning in digestive process. It features teeth and tongue that are both accessory organs of digestion as well as saliva. The teeth are responsible for tearing, biting and churning of food. Tongue is responsible for determining taste of the food, mixing them and pulling bolus down the esophagus in the process of swallowing or deglutition. The salivary glands release saliva that lubricates the food for easy swallowing and pass to esophagus and it contains the salivary amylase that is responsible for breakdown of carbohydrates. Saliva is a watery solution containing mucus, mineral ions and digestive enzymes. The enzyme is secreted by the salivary glands are parotid glands, submandibular glands and sublingual glands. Parotid glands are secretes a serous solution that flows through a parotid duct leading to the cheek wall across from the second upper molar. Submandibular glands are produce mostly serous fluid and mucous fluid. Sublingual
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