The Digestive System a • By: Sabrina Perna
Outline: • The Digestive System • The Mouth • The Pharynx and The Esophagus • The Stomach • The Small Intestine • The Large Intestine • The Rectum and Anus • The Pancreas • The Liver • The Gallbladder • The GERD disease • Fun Facts • Bibliography
The Digestive System • Digestive System: the breaking down of food you eat into smaller parts. • This food turns into energy your body needs. • No food > No energy > Weak > Sick > DIE. • All the organs are joined by the digestive tract. • The tract is made up of muscles that help food move along it. • This process doesn’t stop while you are living
The Mouth • The Mouth: the mouth is the first organ that breaks food into smaller pieces by chewing it. • Saliva mixes with the food to make it softer so the body can absorb it later. • Most known tissues included in the mouth are: -Teeth -Salivary Glands -Tongue - Gums Cells: -Epithelial Cells -Stem Cells
The Pharynx and The Esophagus • The pharynx is the throat which is a passageway for food and air. • After that, the chewed food goes down the esophagus, all the way to the stomach. • Peristalsis are muscle contractions that force food to go down. • Mucosa is a layer of muscle that lines the esophagus. • The Squamous Epithelium is the inner wall of the esophagus. • Squamous cells are found in the esophagus.
The Stomach • The stomach secretes acids and enzymes which mixes and grinds the food. • The food keeps breaking into smaller and smaller pieces until it turns to liquid or paste. • The stomach has 4 types of tissues: -Epithelial: covers and lines the organ -Connective: connects, binds, separates or support organs -Nervous: composed of nerve cells -Muscle: controls movement of food.
The Small Intestine • The small intestine keeps breaking down the food with enzymes and absorbs nutrients. • It is made up of 3 parts: -The duodenum: continues the process -The jejunum: absorbs nutrients -The ileum: also absorbs nutrients. • The small intestine’s inner wall is covered with villi, finger like structures that also absorb nutrients. • Cells: -Goblet cells -Endocrine cells -Exocrine cells -Absorptive cells
The Large Intestine • The large intestine removes water from the undigested matter and form solid waste that can be excreted. • It is made up of different sections: -The cecum -The ascending colon -The transverse colon -The descending colon -The sigmoid colon • Cells: Goblet Cells
Rectum and Anus • The rectum is where the waste is hold until they leave the system. • The anus is the opening of the rectum and this is where waste leaves through. • When the waste is going to be released, the sphincters (muscle) relax and the rectum contracts, releasing the waste through the anus. • Internal Anal Sphincters keeps us from going to the bathroom when we are asleep. • External Anal Sphincters holds the waste until we get find a bathroom
The Pancreas • The pancreas secrete enzymes that help digest proteins, fat, and carbohydrates. • This enzymes are send to the duodenum in the small intestine by ducts (channels). • Cells: -Red Blood Cells -Endocrine Cells -Duct Cells -Delta Cells
The Liver • The liver makes and secrets bile. • It also purifies blood that comes from the small intestine holding nutrients just absorbed. • Bile helps the body absorb fat. • Bile also travels to the small intestine by ducts. • Cells: -Epithelial Cells
The Gallblader • The gallbladder stores bile that the small intestine doesn’t need. • When you eat, the gallbladder contracts and sends the bile to the small intestine. • Cells: -Squamous Cells -Epithelial Cells
The GERD Disease • The gastroesophageal reflux disease (GERD) • It is a disease when the esophageal sphincter ( a muscle that connects the esophagus and the stomach) allows acidic contents of the stomach to move back up into the esophagus. • Causes: acid reflux or getting bile into the esophagus. • Symptoms: burning chest pain, vomiting, and coughing. • Treatment: diet changes, medications, drugs and surgery if necessary. • It can be cured, but it can come back.
Fun Facts The small intestine is actually larger than the large intestine, it is about 20 feet long! You can live without an appendix. Food can stay in your stomach for 2 to 3 hours The stomach can hold 1 liter of food. You can swallow upside down because the muscles in your esophagus are strong enough to move the food. This process takes a couple of days but it keeps on going.
Bibliography • http://www.enchantedlearning.com/subjects/anatomy/digestive • http://digestive.niddk.nih.gov/ddiseases/pubs/yrdd/ • http://www.webmd.com/heartburn-gerd/your-digestive-system • http://kidshealth.org/teen/your_body/body_basics/digestive_system.html# • http://www.cliffsnotes.com • The Digestive System. By: Christine Taylor-Butler