Science 1

• INGESTION

  -is a process of taking food, drink, or other substances into the body by swallowing or absorbing it
• DIGESTION -is a process of breaking down of food into small pieces.
• TYPES OF DIGESTION

  1. Mechanical Digestion - physical breakdown of large pieces of food into smaller pieces

  2. Chemical Digestion - carried out by the enzymes that speed up the chemical reaction.
• ABSORPTION -is the process by which food molecules move into the blood stream to be carried to the cells of the body.
• ASSIMILATION -incorporation of food molecules into the cells of the body to be used as energy, structural materials or storage products.
• EGESTION -is an act of excreting unusable or undigested material from a cell, as in the case of single-celled organisms, or from the digestive tract of multicellular animals.
• MOUTH

  It breaks down the food by your teeth as a means of mechanical digestion. The pieces mix with saliva which is, a watery liquid made by the salivary glands . It softens and wets the food in the mouth and also initially starts chemical digestion through the enzymes present in it.
• ESOPHAGUS

  A muscular tube through which food passes from the mouth into the stomach The wavelike contraction of the food tube is called peristalsis .
• STOMACH

  A big muscular pouch where digestion begins. It is made up of muscles that churn and help mix the food with gastric juices and acids and break it into even smaller pieces. Other enzymes such as lipase and protease help breakdown proteins in the stomach and fats in the small intestine.
• SMALL INTESTINE

  Absorption of food particles takes place here. The walls contain many folds that are lined up with tiny fingerlike protrusions called villi and microvilli where nutrients pass through
• LARGE INTESTINE

  known as colon which absorbs water, secretes mucus and eliminates undigested materials.
• RECTUM

  stores the feces
• ANUS

  opening where the feces is eliminated through the process of defecation
• LIVER

  secretes bile, a greenish fluid that emulsifies fats and neutralizes the stomach acid and increase the efficiency of digestion and absorption
• GALL BLADDER

  where bile is stored
• PANCREAS

  Secretes digestive enzymes that breakdown proteins, carbohydrates, and fats. It also makes insulin , the chief hormone in the body for metabolizing sugar.
• Food


  Any nutritious substance that people or animals eat or drink or that plants absorb to maintain life and growth
• Once the food has been chewed and releases salivary amylase in the mouth, and begins to pass thru the esophagus and stomach, it will be called as the bolus of food
• When it reaches the stomach of an individual and mixed up with different digestive enzymes such as pepsin, the food is now called as chyme until it reaches the small intestine
• After the food has been digested, the waste material will be now called as the feces or the fecal material which will then leaves the body thru the process called excretion of solid waste material.