Digestion Digestion l Your digestive system is uniquely

Digestion

Digestion l Your digestive system is uniquely constructed to perform its specialized function of turning food into the energy you need to survive and packaging the residue for waste disposal.

Digestion l Label the diagram with the following parts of the digestive system: l 1)Mouth 2) Salivary Glands 3) Gall Bladder 4) Liver 5) Pancreas 6) Small Intestine 7) Esophagus 8) Stomach 9) Large Intestine 10) Rectum 11) Anus l l l l l

The Mouth l l Digestion starts here Chewing breaks the food into pieces that are more easily digested, while saliva mixes with food to begin the process of breaking it down into a form your body can absorb and use.

Salivary Glands Saliva or spit, produced by the salivary glands (located under the tongue and near the lower jaw) l Saliva begins to break down the food, moistening it and making it easier to swallow l

Gall Bladder l The gallbladder stores and concentrates bile, and then releases it into the small intestine to help absorb and digest fats.

Liver l l The liver filters out harmful substances or wastes, turning some of the waste into more bile. The liver even helps figure out how many nutrients will go to the rest of the body, and how many will stay behind in storage. l For example, the liver stores certain vitamins and a type of sugar your body uses for energy. l The livers main purpose is to turn nutrients into a form the body can use. ie) amino acids to protein

Pancreas The pancreas secretes digestive enzymes into the small intestine l These enzymes break down protein, fats, and carbohydrates. l The pancreas also makes insulin, secreting it directly into the bloodstream. Insulin is the chief hormone for metabolizing sugar l

Small Intestine l l l A 22 -foot long muscular tube that breaks down food Contents of the small intestine start out semisolid, and end in a liquid form after passing through the organ. The small intestine breaks down the food mixture even more so your body can absorb all the vitamins, minerals, proteins, carbohydrates, and fats.

The Esophagus l l l Attaches the mouth to the stomach The esophagus receives food from your mouth when you swallow. The esophagus will contract pushing the food down into the stomach

The Stomach l l l The stomach is a hollow organ Food is still being broken down When ready the stomach releases the food into the small intestine Widest part of the digestive system Shaped like the letter J. It has three important jobs: l l l to store the food you've eaten to break down the food into a liquidy mixture to slowly empty that liquidy mixture into the small intestine

Large Intestine l l l A 6 -foot long muscular tube that connects the small intestine to the rectum. The large intestine is a highly specialized organ that is responsible for processing waste so that emptying the bowels is easy and convenient. Stool, or waste left over from the digestive process, is passed through the colon by means of peristalsis, first in a liquid state and ultimately in a solid form. As stool passes through the colon, water is removed. It normally takes about 36 hours for stool to get through the colon. The stool itself is mostly food debris and bacteria. When the descending colon becomes full of stool, or feces, it empties its contents into the rectum to begin the process of elimination.

Rectum • The last part of the large intestine is the rectum, which is where feces (waste material) is stored before leaving the body through the anus.

Anus l The anus makes the exit point of the digestive tract where feces leave the body.

Absorption and Transport of Nutrients l Carbohydrates: l l Proteins: l l l Shortest amount of time to digest Broken down into simple sugars called glucose GLUCOSE: is the body’s basic fuel supply Broken down into amino acids Used for energy Fats: l l Longest to digest Are changed into fatty acids for the body to use

Digestive Juices l Bile: l l Pancreatic: l l l Helps your body digest and absorb fats. Produced in the liver Stored in the gall bladder Helps to break down carbohydrates, proteins and fats Produced in the pancreas Intestinal: l l Produced in the small intestine Works with other juices to break down food.

Absorption After digestion the nutrients are absorbed into the bloodstream l Most absorption take place in the small intestine l After absorption FIBER is left in the small intestine l Waste material goes to the large intestine l

Terms l Define the following terms from the text book: Oxidation l Automatic Processes l Physical Activities l Villi l Basal Metabolism l

Questions l l l l l Why is chewing your food important? In what body organ does digestion start? How much food can your stomach hold? What is chyme? Why are villi important in digestion? What is another name for your colon? What is the difference between glucose and glycogen? If someone has a piece of the small intestine removed because of a disease, what nutritional problems could result? What is the main purpose of the liver? If someone had a small piece of the small intestine removed because of a disease, what nutritional problems could result?