Digestive System 1st Hour Team Hannah

Include the following on your slide: Name of organ Description of structure Function of organ Identify if there is mechanical &/or chemical digestion occurring Picture of the organ Identify any secretions produced Function of secretions Use only 1 slide. Make sure it is neat & easy to read.

Mouth The mouth is the beginning of the digestive tract. Chewing breaks the food into pieces that are more easily digested(Mechanical) Saliva mixes with food to begin the process of breaking it down into a form your body can absorb and use. (Chemical) Secretes Saliva- contains the Amylase enzyme which breaks down starch

pharynx the membrane-lined cavity behind the nose and mouth, connecting them to the esophagus. Sends foods to the esophagus No digestion Mucous for lubrication

Esophagus The esophagus is a muscular tube connecting the throat with the stomach. The esophagus is about 8 inches long, and is lined by moist pink tissue called mucosa. Its function is to carry food, liquids, and saliva from the mouth to the stomach. Mucus is the only secretion in the esophagus, it aids in lubrication

Stomach -The stomach is a rounded, hollow organ located just inferior to the diaphragm in the left part of the abdominal cavity. -The main function of the stomach is to break down and digest food in order to extract necessary nutrients from what you have eaten. -The stomach starts chemical digestion of protein. Secretions from the stomach lining consist of about two liters of hydrochloric acid (HCl), pepsin, and other fluids that make up gastric fluids each day. The fluid is extremely acidic and it helps kill bacteria and other pathogens that may have been ingested. -Produces mucus (coats and lubricates the gastric surface), acid (important for activation of pepsinogen and inactivation of ingested microorganisms such as bacteria.), proteases (largely responsible for the stomach's ability to initiate digestion of proteins), and hormones (a peptide that is important in control of acid secretion and gastric motility).

Small Intestine

Large Intestine The large intestine, or the large bowel, is the last part of the gastrointestinal tract and of the digestive system in vertebrates The major function of the large intestine is to absorb water from the remaining indigestible food matter and transmit the useless waste material from the body Chemical Absorption: water, sodium ions and chloride ions. Secretion: bicarbonate ions and mucus

Pancreas -a large gland behind the stomach that secretes digestive enzymes into the duodenum. Embedded in the pancreas are the islets of Langerhans, which secrete into the blood the hormones insulin and glucagon. Function: secreted into the small intestine to further break down food after it has left the stomach. Chemical or Physical digestion?- produce enzymes needed for chemical digestion Secreations- Pancreatic juice is composed of two secretory products critical to proper digestion: digestive enzymes and bicarbonate. The enzymes are synthesized and secreted from the exocrine acinar cells, which bicarbonate is secreted from the epithelial cells lining small pancreatic ducts.

Liver -The liver is a large, meaty organ that sits on the right side of the belly -The liver secretes bile that breaks down fat in the intestines and also filters blood coming from the digestive tract -no Digestion -Produces the secretion, Bile -Bile breaks down fat and is stored in the Gallbladder

Gallbladder The Gallbladder is a small, thin-walled green sac that snuggles in a shallow fossa in the inferior surface of the liver. It’s primary function is to store and concentrate bile to be used in Chemical Digestion Bile is a yellow-brown digestive enzyme produced by the liver. Bile contains bile acids, which are critical for digestion and absorption of fats and fat- soluble vitamins in the small intestine.