Digestive System Leshel Ponce, Elizabeth Cobian, Sasha Padilla Period 3

What is the Digestive System? ●The Digestive system is a group of organs that work together to convert food into energy and basic nutrients to feed the entire body.

Macromolecules ●travel through digestive tract as a carbohydrate, like starch and sugar but cannot be digested ●provide nutrition -Carbohydrates -Protein -Nucleic Acids -Lipids

Macromolecules ●Carbohydrates- provide materials to build cell membranes, and build quick energy for cells Ex: Monosaccharides, disaccharides, polysaccharides ●Lipids-energy source Ex: Fats, oils ●Nucleic Acids- growth and development of organism Ex: DNA and RNA ●Protein- build and repair muscles and cell membranes, fight infections Ex: antibodies, most enzymes and hormones

●passage along which food passes through the body ○mouth ○pharynx ○esophagus ○stomach ○small intestine ○large intestine ○rectum ○anus Alimentary Canal

Accessory Organs An organ that helps with digestion, but is not part of the digestive tract teeth tongue salivary glands liver gallbladder pancreas

Mouth Function: receives food, breaks solid particles into smaller particles using the teeth then mixes them together with help of the tongue and saliva ●Macromolecules: ○carbohydrates, lipids

Salivary Glands Parotid Gland Watery serous fluid Sublingual Gland thick mucous fluid Submandibular Gland mixed serous and mucous fluid

Enzymes Mouth Salivary Amylase - Breaks apart starch into oligosaccharides Lingual Lipase - Breaks down fats in mouth

Pharynx Location: throat, connects nasal and oral cavity to the esophagus Function: serves as a passageway to the esophagus

Esophagus Location: runs behind the trachea, heart, and in front of the spine Function: passageway from pharynx to the stomach mucus moistens and lubricates inner lining making it easy for food to pass through Peristalsis wave like muscle contractions that help move food along

Stomach Locations: hangs inferior to the diaphragm in the upper left portion of the abdominal cavity ●Function: receives food from the esophagus mixed it with gastric juices initiates digestion of proteins carries on limited absorption moves food into small intestine ●Macromolecules: ○ lipids, protein, nucleic acids

Gastrin ● come from G cells located in gastric pits ●stimulates gastric glands to secrete enzymes and acid ●help to secrete pepsinogen and hydrochloric acid ●secretion caused by food arriving in stomach ●affects pancreas, liver, and intestines

Motilin ●produced from endocrine cells of duodenal mucosa ●increases migrating myoelectric complex component of gastrointestinal motility ●stimulates pepsin production ●affects stomach and small intestine

Ghrelin ●produced in stomach and upper intestine ●tells the brain that the body needs to be fed

Enzymes Stomach Pepsin - Breaks proteins into polypeptides Mucus - Protects stomach from pepsin and hydrochloric acid Lipases - Breaks down fats

Liver Location: upper right quadrant of the abdominal cavity, inferior to the diaphragm Function: produces bile that emulsifies fat

Pancreas Location: extends horizontally across the posterior abdominal wall with its head on the Function: Produces and secretes pancreatic juice containing digestive enzymes and bicarbonate ions into the small intestine

Secretin comes from hydrochloric acid passing from stomach into duodenum signals secretion of sodium bicarbonate in pancreas and liver regulate duodenum activity affects pancreas and liver

Gallbladder Location: pear shaped sac in a depression on the inferior surface of the liver Function: stores bile and introduces it to the small intestine

Cholecystokinin ●come from mucosal epithelial cells in small intestine ●stimulate release of digestive enzymes in pancreas and empties bile in gallbladder ●improves digestion ●affects gallbladder, small intestine, and pancreas

Small Intestine ●Location: tubular organ that loops and coils to fill most of the abdominal cavity ●Function: receives secretion from the pancreas and liver completes digestion of nutrients absorbs the products of digestion transports the remaining residues to the large intestine ●Macromolecules: carbohydrates, lipids, proteins, and nucleic acids

Gastric Inhibitory Peptide ●comes from mucosal epithelial cells in small intestine ●increases insulin secretion in response to infusions of glucose ●affects glucose absorption and small intestine

Enzymes Small Intestine Lipases - Breaks down fat Amylases - Breaks down large carbohydrate chains Proteases - Breaks down protein Bile Salts - Breaks down fat Maltase - Breaks maltose into two glucose

Enzymes Small Intestines Continue… Nucleosidases - Breaks down nucleotides into base, sugar, and phosphate Sucrase - Breaks sucrose into glucose and fructose Dipeptides - Breaks down peptides into amino acids Carbohydrase - Breaks starch into glucose

Large Intestine Location: tubular organ that begins in the lower right side of the abdominal cavity and descends into the pelvis Function: absorbs ingested water and electrolytes remaining in the alimentary system reabsorbs and recycles water and remnants of digestive secretion to form feces

Rectum Location: next to the sacrum, ending at the end of the coccyx Function: serves as storage and it regulates the elimination of feces

Anus Location: tip of the coccyx Function: contains muscles under voluntary control to eliminate feces

Digestion Structures Mouth (Mechanical + Chemical) Pharynx (Mechanical) Esophagus (Mechanical) Stomach (Mechanical) Small Intestine (Chemical) Large Intestine (Chemical) Anus (Mechanical)

Enzymes Most Important

Bibliography “Digestive System.” Inner Body. N.p., n.d. Web. 1 Feb “Extraordinary Lives Start With a Great Catholic Education.” Dufferin-Peel Catholic District School Board. N.p., n.d. Web. 1 Feb “’How to Help Prevent Occasional Bouts of Bloating, Gas, and Indigestion with Two Very Specialized Formulas*.’” Dr. Mercola. N.p., n.d. Web. 1 Feb Kitses. N.p., n.d. Web. 1 Feb “Mechanical and Chemical Digestion.” The Smart Living Network. N.p., 10 Apr Web. 1 Feb “Textbook Innovation.” Boundless. N.p., n.d. Web. 1 Feb