Digestive System

• Muscle cells


  Can contract (shorten) and get shorter
• Muscle cells


  • They contain protein
  • They have fibers which can change this length
  • Muscle cells and tissues work together to provide the movement needed to carry out body functions
• A tissue is a group of cells with similar structure and function
• An organ is a group of tissues working together for a specific function
• Foods contain three main nutrients: carbohydrates, proteins, and lipids (fats)
• Digestion in the mouth

  1. Food is chewed

  2. Enzymes in saliva begin to digest the starch into smaller sugar molecules
• Enzyme


  A catalyst that speeds up chemical reactions in the body
• Digestion in the stomach

  1. Enzymes begin the digestion of proteins

  2. The stomach churns the food into a liquid, increasing the surface area for enzymes
• Digestion in the small intestine

  1. Enzymes are released from the pancreas that continue the digestion of starch and protein

  2. Lipids (fats) are also digested

  3. The small molecules are absorbed into the bloodstream