Digestive System

1a. Review. Explain the function of the digestive system.
The digestive system converts food into small molecules that can be used by the cells of the body.
1b. Compare and Contrast. What is thedifference between mechanical digestion and chemical digestion?
The mechanical digestion only mixes the food with the gastric juice, the enzymes, etc. forming a mixture called chyme and during thechemical digestion glands start releasing enzymes, such as pepsin, other glands produce mucus to protect the stomach.
2a. Review. List the structures that food travels through during digestion and givethe function of each.
• Mouth: Its function its chewing and mixing food with saliva making a mixture named “bolus”.
• Epiglottis: cartilage tissue.
• Esophagus: Tube that transport food into thestomach, it has contractions that force food to move toward the stomach.
• Cardiac sphincter: after food passes into the stomach, a thick ring of muscle closes the esophagus.
• Stomach: Muscle thatchurns food with gastric juice breaking up food and forming a liquid mixture called chyme. Protein digestion begins.
• Small intestine: The chyme is slowly released. The digestion of fats occurswith the help of bile, enzymes form the pancreas and the duodenum complete digestion. Nutrients are absorbed.
• Large intestine: absorbs water and transports the undigested material.
2b. Relate causeand effect. Some people have a disorder in which their stomach muscles cannot contract and churn food. What effect do you think this has on the length of time food stays on the stomach.
The foodwould stay longer in the stomach because it wouldn´t be divided and completely digested, the mixture of the food with gastric juice wouldn´t be completely liquid and mixed.
The small intestine wouldn´tbe able to do it´s function because the food wouldn´t be able to pass liquid, slowly and digested so the nutrients won´t be able to be absorbed.
3a. Review. Explain how nutrients are absorbed....