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During the second week of development, the embryo grows and begins to surround and envelop portions of this sac. Pulpitis Radicular cyst Periapical abscess. The attachment of the suspensory muscle to the diaphragm is thought to help the passage of food by making a wider angle at its attachment. Consider giving these a try. Parotid gland duct Submandibular gland duct Sublingual gland duct. Hydrogen ions secreted from the inner lining of the gallbladder keep the bile acidic enough to prevent hardening.

Introduction

Human digestive system

The pharynx, or throat, is a funnel-shaped tube connected to the posterior end of the mouth. The pharynx is responsible for the passing of masses of chewed food from the mouth to the esophagus. The pharynx also plays an important role in the respiratory system, as air from the nasal cavity passes through the pharynx on its way to the larynx and eventually the lungs. Because the pharynx serves two different functions, it contains a flap of tissue known as the epiglottis that acts as a switch to route food to the esophagus and air to the larynx.

It carries swallowed masses of chewed food along its length. At the inferior end of the esophagus is a muscular ring called the lower esophageal sphincter or cardiac sphincter.

The function of this sphincter is to close of the end of the esophagus and trap food in the stomach. The stomach is a muscular sac that is located on the left side of the abdominal cavity, just inferior to the diaphragm. In an average person, the stomach is about the size of their two fists placed next to each other. This major organ acts as a storage tank for food so that the body has time to digest large meals properly. The stomach also contains hydrochloric acid and digestive enzymes that continue the digestion of food that began in the mouth.

It is located just inferior to the stomach and takes up most of the space in the abdominal cavity. The entire small intestine is coiled like a hose and the inside surface is full of many ridges and folds.

These folds are used to maximize the digestion of food and absorption of nutrients. The liver is a roughly triangular accessory organ of the digestive system located to the right of the stomach, just inferior to the diaphragm and superior to the small intestine. The liver weighs about 3 pounds and is the second largest organ in the body.

The liver has many different functions in the body, but the main function of the liver in digestion is the production of bile and its secretion into the small intestine. The gallbladder is a small, pear-shaped organ located just posterior to the liver. The gallbladder is used to store and recycle excess bile from the small intestine so that it can be reused for the digestion of subsequent meals.

The pancreas is a large gland located just inferior and posterior to the stomach. The pancreas secretes digestive enzymes into the small intestine to complete the chemical digestion of foods. The large intestine is a long, thick tube about 2. It is located just inferior to the stomach and wraps around the superior and lateral border of the small intestine.

The large intestine absorbs water and contains many symbiotic bacteria that aid in the breaking down of wastes to extract some small amounts of nutrients. Feces in the large intestine exit the body through the anal canal. The digestive system is responsible for taking whole foods and turning them into energy and nutrients to allow the body to function, grow, and repair itself. The six primary processes of the digestive system include:. The first function of the digestive system is ingestion, or the intake of food.

The mouth is responsible for this function, as it is the orifice through which all food enters the body. The mouth and stomach are also responsible for the storage of food as it is waiting to be digested.

This storage capacity allows the body to eat only a few times each day and to ingest more food than it can process at one time. In the course of a day, the digestive system secretes around 7 liters of fluids. These fluids include saliva, mucus, hydrochloric acid, enzymes, and bile. Saliva moistens dry food and contains salivary amylase, a digestive enzyme that begins the digestion of carbohydrates.

Mucus serves as a protective barrier and lubricant inside of the GI tract. FGF19 fibroblast growth factor FGFR4 fibroblast growth factor receptor 4. FXR farnesoid X receptor. FXRE farnesoid X receptor response element. GLP-1 glucagon-like peptide 1.

GLUT2 glucose transporter type 2. GPCRs G protein-coupled receptors. GSK3 glycogen synthase kinase 3. HDL-C high density lipoprotein cholesterol. I-BABP intestinal bile acid-binding protein.

IBD inflammatory bowel disease. KLF11 Kr├╝ppel-like factor KRAS Kirsten rat sarcoma viral oncogene homolog. LBD ligand binding domain. LRH-1 liver receptor homolog MRP2 multidrug resistance-associated protein 2. PEPCK phosphoenol pyruvate carboxykinase.

SHP small heterodimer partner. SREBP-1c sterol regulatory element-binding protein 1c. STAT3 signal transducers and activators of transcription 3. T2D type 2 diabetes.

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