Monday, October Pick up a little man from the front table. Color and glue it into your journal on the next available page.

Transcription

1 1. Pick up a little man from the front table. Color and glue it into your journal on the next available page. 2. Answer the following question on the same page: How do proteins, lipids and carbs impact you? Monday, October 5

2 How long is the average Digestive System?

3 1. Mark off 3 inches (7 cm) of string to represent your mouth. 2. Add 10 inches (25 cm) for your esophagus. 3. Add 6 inches (15 cm) for your stomach. 4. Add 18 inches (5.5 meters) for your small intestine. 5. Add 5 feet (1.5 meters) more for your large intestine. 6. Measure the entire length of the string and record the results.

4 What is the digestive system? The digestive system is the system within the body that breaks down food into substances that cells can absorb and use and eliminates any leftover wastes.

5 How is food digested? Food is digested in two primary ways: chemical & mechanical (physical) Chemical Breakdown of large molecules into smaller molecules. Assisted by chemicals in the body including saliva, pancreatic and gastric juices and bile. Mechanical (physical) Breaking down of food by teeth into smaller pieces. Movement of food through the digestive system known as peristalsis.

6 Mouth The digestive system begins in the mouth. Both mechanical and chemical digestion take place in the mouth. Mechanical Teeth, with the help of strong jaw muscles break and crush the food.

7 Mouth - Chemical Chemical As you chew, food is moistened by saliva. Saliva includes an enzyme that begins the chemical digestion of starches in food. Salivary glands are around the mouth and face.

8 Esophagus Once food has been chewed, it is then swallowed. The food moves through the throat into a long tube called the esophagus. Waves of muscle contractions called peristalsis move the food into the stomach. Peristalsis is part of mechanical digestion.

9 Stomach The stomach is a muscular bag that crushes food and contains acids and enzymes for killing bacteria and breaking down proteins. The stomach lining produces strong digestive juices known as gastric juice. These juices create chemical reactions in the stomach that begin the process of breaking down proteins. The food is reduced to a soupy mixture called chyme.

10 Pancreas While food in the digestive system does not pass through the pancreas, it is vital in the breakdown of molecules. The pancreas is responsible for secreting pancreatic juice that contains enzymes to further break down carbohydrates, proteins, lipids(fats)and nucleic acids in the chyme.

11 Liver The liver is another organ that doesn t directly breakdown food. It is responsible for creating bile, a compound that assists in the breakdown of large fats into very small fat droplets.

12 Gallbladder The gallbladder is much like the liver, not an organ of which food passes through for digestion, but it certainly assists. The gallbladder is a small organ where bile created in the liver, is stored before it s released to the small intestine.

13 Small Intestine The small intestine is where the newly created chyme heads after a few hours in the stomach. The small intestine is a muscular tube where most chemical digestion takes place and most nutrients are absorbed. Nutrients are broken down small enough to pass through the inner lining of the small intestine and into the blood through diffusion. Within the folds of the small intestine are tiny fingerlike projections called villi. Villi contain blood and lymph vessels that absorb nutrients from the food as it passes. villi

14 Large Intestine After food passes through the small intestines, it moves to the large intestines. In the large intestine, water and nutrients are absorbed. Any remaining solid material is then compacted and stored as feces.

15 Rectum & Anus The rectum is the last part of the large intestine. The rectum stores feces until it can be expelled. Feces pass to the outside of the body through an opening called the anus. It takes approximately 24 hours for a meal to make the full journey through a person s digestive system.