Emma_Granich_SBI3U_Mod8_Assigment by Emma Granich

Intro to the Digestive System

emmagranich — 2015-11-10 12:53:20 UTC

The digestive system is one of the most essential organ system in the body. The digestive system breaks down of large organic materials into smaller pieces. It provides nutrients and releases wastes and nutrients that are not used. The digestive system relies on other organ systems to function properly and organ systems rely on the digestive system to function. There are four parts of digestion, ingestion, digestion, absorption, and egestion. Ingestion is when nutrients are taken in, digestion is breaking down of organic molecules into smaller molecules, absorbtion is when nutrients that have been digested are moved to other body tissues, and egestion is when wastes are removed from the body.

1. Mouth

emmagranich — 2015-11-10 13:16:45 UTC

The process of digestion starts to occur in the mouth. The mouth is made up of several parts that break down food into smaller pieces. The food gets broken down in a process known as mechanical digestion. When the food is in the mouth the brain sends out a message to the salivary glands, to produce saliva. This saliva contains ptyalin, which is an enzyme that helps break down food by softening it. The teeth then breaks down the food into smaller pieces. The tongue then pushes the food towards the back of the mouth. The soft palate guides the food down into the food pipe, and stops food from going into the nose cavity. Once the food enters the esphagus, digestive enzymes break down the food into smaller pieces.

2. Esophagus

emmagranich — 2015-11-10 13:17:09 UTC

After food is broken down by the mouth and swallowed, the food goes into a muscler food tube known as the esophagus. The esophagus moves lipids and foods from the mouth to the stomach through a channel or series of muscle contractions known as peristalsis. When the food is swallowed, the food moves from the mouth to the throat(pharynx). The upper esophageal sphincter opens up, allowing food to go through. The muscle contractions or peristalsis pushes the food down through the lower esophageal sphincter into the stomach.

3. Stomach

emmagranich — 2015-11-10 13:17:54 UTC

After it goes through the esophageal sphincter, the food goes into the stomach. The stomach is made up of 3 sections, the fundus, body, and the pyloric antrum. The stomach is made of a inner layer(mucosa membrane), muscle layer, and an outer layer(serosa). The mucosa layer creates enzymes and stomach acids to eliminate bacteria and to break down food. The muscles begin to contract, when the stomach is empty, and the mucosa produces creates rugal folds. When the stomach is full, the rugal folds and muscles start to move outwards. The esophageal sphincter splits the stomach from the esophagus to prevent gastric juices and food from going back to the esophagus. The gastric juices then breaks down food. These gastric juices are made up of mucus, hydrochloric acid, and pepsinogens. Mucus coats and protects the inner layer of the stomach from acids. Hydrochloric acid(HCL) kills the deadly substances that are ingested with food. Hydrochloric acid converts pepsinogen into pepsin, which is an enzyme that digests proteins
The stomach muscles contract together , grinding, crushing, mixing food in a substance known as chyme. The pyloric sphincter splits the stomach and the duodenum from each other to retain food and gastric juices in the stomach until it is a liquid. Each time, the stomach muscles contract, a small amount of chyme is released into the duodenum. This process continues untill all of the food turns into a liquid and enters the duodenum. Although, the stomach breaks down the food, it does not absorb the nutrients. Nutrients go towards the small intestine to be absorbed.

4. Small Intestine

emmagranich — 2015-11-10 13:23:28 UTC

After the food is broken down in the stomach, it's nutrients duodenum and minerals are absorbed by the small intestines. There are 3 parts of the intestine, duodenum, jejunum, and ileum. The food first goes through the duodenum through the pyloric sphincter. When acids are in the small intestine, prosecretin becomes converted into secretin. Secretin becomes absorbed into the blood stream, and is transported to the pancreas, where it indicates a solution that contains bicarbonate ions. Bicarbonate ions (HCO3-) are transported to the small intestine to neutralize Hydrochloric acid(HCL) in gastric fluid and to increase the pH levels from 2.5 to 9.0. This deactivates the pepsin. The secretin releases stomach acids to protect the small intestine. The pancreatic secretions are made up of enzymes that breakdown proteins, carborhydrates, and lipids. Trypsinogen(an enzyme that digests proteins) is released from the pancreas. This enzyme then goes to the small intestine,where it is converted into trypsin, by an enzyme known as enterokinase. The long chain of polypeptides is broken down into a shorter chain by the enzyme trypsin. The pancreas releases another group of enzymes, known as erepsins. Short chains of peptides are broken down into amino acids, by the enzyme erepsin. Amaylase enzymes are released by the pancreas. The medium sized chains are broken down into disaccharides. These disaccharides enzymes are released from the small intestine to finish the digestion of carbohydrates. amylase breaks down amylose, and breaks down disaccharidases
into monosaccharides. Lipases are enzymes released from the pancreas that break down lipids (fats). There are two types of enzymes that digest lipids, pancreatic lipids which breaks down fats into glycerol or fatty acids and phospholipids which breaks down phospholipids. The duodenum receives bile from the liver and gallbladder, as well as pancreatic enzymes.

6. Large Intestine

emmagranich — 2015-11-10 13:27:49 UTC

After the digestion of the chemicals in the stomach and the small intestines are complete,the food enters the large intestine. The large intestine absorbs nutrients and water. The large intestine is made of 4 layers, mucosa,submucosa, muscularis, and serosa. The mucosa layer is made of epithelial tissue and the submucosa is made of blood vessels, nerves, and connective tissue. Muscularis is made of many layers of visceral muscle cells and serosa is made of a thin layer of squamous epithelial tissue. The large intestine is responsible for converting food into feces and absorbing vitamins. Chyme goes into the large intestine or colon from the small intestine. The chyme is transported through the the cecum, and is transported from one haustra to another through peristalss. While chyme is transported, the bacteria digests substances in the chyme that cannot be normally be digested. Chyme is converted into feces and releases vitamins. As a result of this, carbon dioxide, methane and other gases are created. The colon is made up of villi, which allow nutrients to move towards theblood capillaries and lymph vessels. This allows nutrients to be moved throughout the human body. Mucous transports the food to the rectum, where the food is released from the body.

7. Rectum/Anus

emmagranich — 2015-11-10 13:29:18 UTC

After the food has been digested, the food is placed inside the rectum. After a certain period of time, the food is removed from the body through the anus. The food takes on the form of a stool or a poop. The cycle of digestion starts over again to digest new food that has entered the system.

Mouth Diagram

emmagranich — 2015-11-12 22:30:52 UTC

Esophagus Diagram

emmagranich — 2015-11-13 17:40:28 UTC

Stomach Diagram

emmagranich — 2015-11-13 19:19:59 UTC

Small Intestine Diagram

emmagranich — 2015-11-13 20:28:21 UTC

Large Intestine Diagram

emmagranich — 2015-11-14 02:10:47 UTC

Rectum/Anus Diagram

emmagranich — 2015-11-14 03:13:52 UTC

5. Liver and Gallbladder

emmagranich — 2015-11-14 03:29:29 UTC

The liver creates bile, gets rid of deadly substances and glucose. Bile salts helps speed up the pace of digestion when it is not occurring. Bilesalts are placed inside the gallbladder. While fat is broken down in the small intestine, the liver creates cholecystokinin(CCK). CCK is moved to the gallbladder, where bile salts are released. The bile salts breakdown food by physical digestion.

Liver and Gallbladder Diagram

emmagranich — 2015-11-14 03:31:49 UTC

Resources

emmagranich — 2015-11-14 03:53:29 UTC

Websites "Large Intestine." InnerBody. Web. 10 Nov. 2015. <http://www.innerbody.com/anatomy/digestive/large-intestine>.

"Small Intestine." Small Intestine. Web. 9 Nov. 2015. <http://www.kidport.com/reflib/science/HumanBody/DigestiveSystem/SmallIntestine.htm>

"Digestion." Digestion Site Wide Activity RSS. Web. 9 Nov. 2015. <http://digestion.ygoy.com/2010/11/01/mechanical-digestion-in-the-mouth/>.

"Stomach - Digestive Disorders." Merck Manuals Consumer Version. Web. 9 Nov. 2015. <http://www.merckmanuals.com/home/digestive-disorders/biology-of-the-digestive-system/stomach>.

Images
"Digestive Tract - American Nurse Today." American Nurse Today. 6 Aug. 2014. Web. 9 Nov. 2015. <http://www.americannursetoday.com/?attachment_id=16015>.
"Human-mouth-anatomy." Wwwokaidimaltacom. Web. 8 Nov. 2015. <http://www.okaidimalta.com/human-mouth-anatomy/human-mouth-anatomy/>. "IBC Integrated Healthcare & Wellness Center." IBC Integrated Healthcare & Wellness Center. Web. 7 Nov. 2015. <http://www.wellnessibc.com/doc/products.aspx>.
"Application of Oncolytic Viruses for Cure of Colorectal Cancer :: Science Publishing Group." Application of Oncolytic Viruses for Cure of Colorectal Cancer :: Science Publishing Group. Web. 9 Nov. 2015. <http://article.sciencepublishinggroup.com/html/10.11648.j.crj.20150304.13.html>. "Irritable Bowel Syndrome vs. Inflammatory Bowel Disease." HubPages. HubPages. Web. 7 Nov. 2015. <http://hubpages.com/health/Irritable-Bowel-Syndrome-vs-Inflammatory-Bowel-Disease>. "Healthy Life." : Esophagus. Web. 8 Nov. 2015. <http://erwinadr.blogspot.ca/2011/03/esophagus.html?m=1>."Stomach-Gross Anatomy - Health Insurance Quotes." RSS. Web. 8 Nov. 2015. <http://healthtipsinsurance.com/stories/24241/Stomach-Gross-Anatomy.html>. "The Equine Digestive System." The Equine Nutrition Nerd. 28 June 2014. Web. 9 Nov. 2015. <http://equinenutritionnerd.com/2014/06/29/the-equine-digestive-system/>.

Digestive System Diagram

emmagranich — 2015-11-14 03:55:28 UTC