Digestive system

Functions of the digestive system Breaks down food into molecules the body can use absorption of those molecules into the blood and carried throughout the body Wastes are eliminated from the body

Mechanical digestion Happens in the mouth with the teeth Changes the physical form of food Chew Tear Grind Mash mix

teeth

Chemical digestion Changes the chemical composition of food with the aid of digestive enzymes These enzymes help break up large molecules of food into tiny molecules that can be absorbed and used by the cells in the form of nutrition

Phases of digestion Ingestion Movement Digestion Absorption Further digestion

The digestive tract A long muscular tube with many sections and areas Begins with the mouth and ends with the anus

Parts and path of the digestive tract Mouth Pharynx Esophagus Stomach Small intestines Large intestines Rectum anus

mouth Food enters in the oral cavity Tasting Mechanical breakdown of food Secretions of salivary glands Tongue Mixes and rolls food into mashed up bits and pushes toward the pharynx and into the esophagus when swallowing

esophagus A straight muscular tube that connects the mouth to the stomach Takes 4-8 seconds to get to the stomach

stomach J shaped sac Has inner folds called rugae that help make the stomach turn the food into smaller pieces Food is mixed with gastric juices (acid) which breaks food down and kills bacteria that came with the food Mucus lines the stomach so the acid wont eat through the lining Food is converted to chyme after 4 hours (food soup)

Small intestines 20+ foot coiled tube that connects the stomach to the large intestines Has 3 parts Duodenum Jejunum Ileum Digested nutrients absorb through the intestinal walls

Large intestines Aka the colon Larger in diameter but shorter than the small intestines Undigested food from the small intestines comes here Water is absorbed from the undigested food making it a harder solid Waste stays here for 10-12 hours Appendix hangs off the large intestines

Rectum and anus Solid waste stays in the rectum until pushed out or excreted through the anus Anus is the outside opening

Accessory parts of the digestive tract Organs that are not in the digestive tract but help in the digestion Teeth Tongue Salivary glands Liver Gall bladder pancreas

Accessory organs Liver Pancreas Gall bladder Largest gland in the body Stores vitamins and sugar Produces bile Pancreas Produces juices that contain enzymes that goes into the duodenum Gall bladder Stores bile

Fun facts about the digestive system We make 1 to 3 pints of saliva a day Muscles contract in waves to move the food down the esophagus. This means that food would get to a person's stomach, even if they were standing on their head It takes your mouth, esophagus, stomach, small intestine, large intestine, gallbladder, pancreas and liver just to digest a glass of milk An adults stomach can hold approximately 1.5 liters of material The average male will eat about 50 tons of food during his lifetime in order to sustain a weight of 150 pounds A full grown horse’s coiled up intestines are 89 feet long.