Digestive system

• mechanical digestion


  physical breakdown of food into smaller pieces (movement like a machine)

  
• chemical digestion


  when enzymes in liquids break down food into smaller molecules

  
• saliva


  softens food in the mouth; helps break down food into simpler forms; secreted by glands in the mouth

  
• digestive enzymes


  Chemicals that break down food into a form that can be used by the body

  
• bolus


  a small rounded ball of chewed food your mouth and tongue make before swallowing

  
• esophagus


  a muscular tube that food goes down connecting the mouth to the stomach

  
• peristalsis


  involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system

  
• stomach


  a muscular and elastic sac that stores food and breaks it up mechanically and chemically.

  
• chyme


  the partially digested, semiliquid food in the stomach

  
• small intestine


  digestive organ where most chemical digestion and absorption of food takes place. (It is about 20-23 feet long in an adult.)

  
• large intestine


  the last section of the digestive system, where water is absorbed from food and the remaining waste is stored before being eliminated from the body

  
• rectum


  a short tube at the end of the large intestine where waste material is compressed into a solid form before being eliminated

  
• anus


  a muscular opening at the end of the rectum where waste material is eliminated from the body
• Ingestion


  Stage 1: taking food into the mouth

  
• Digestion


  Stage 2: Breaking down food into smaller pieces

  
• Absorption


  Stage 3: The soaking up of dissolved nutrients to be delivered to the body's cells.

  
• Elimination


  Stage 4: the process by which wastes are removed from the body