The Gastrointestinal System Flashcards
The Gastrointestinal System includes
The Upper GI tract (oral cavity, pharynx, esophagus ,stomach) Lower GI tract (small & larger intestine), gallbladder, liver, pancreas
Oral cavity function
Oral cavity: Upper GI tract includes the structure of the oral cavity including the lips, soft and hard palate, uvula, tongue, soft tissues, dental arches, teeth primary and permanent dentition, and salivary glands secreting saliva.
Small Intestine
Small Intestine: Long tube extends from the pyloric sphincter of the stomach to the large intestine. It is divided into the duodenum, jejunum and ileum. Function is to break food down, absorbs nutrients, extracts water.
Chyme is moved into the small intestine by peristalsis. In duodenum, chyme is mixed with pancreatic juices and bile from pancreas and liver/ gall bladder respectively. It emulsifies fat so that the nutrients can be absorbed by the body. The jejunum secretes digestive enzymes to continue digestion. The ileum is a site for absorption of nutrients into the bloodstream so it can be carried to the body tissues.
Function of Gastrointestinal System
To digest and absorb ingested nutrients and to excrete waste products of digestion.
Liver
Large organ removes toxins from blood and helps turn food into fuel and nutrients. Secrete bile to help emulsify (breakdown) fats
located in the upper right-hand portion of the abdominal cavity, beneath the diaphragm, and on top of the stomach, right kidney, and intestines
Gallbladder
Gallbladder: Pear-shaped organ is located under the liver and connects via small ducts. Gallbladder stores bile formed by the liver to help digest fat
Pancreas
Soft, oblong gland is located behind the stomach. It secretes pancreatic juices call enzyme to aid digestion which it secretes into the pancreatic duct, into bile duct and into the duodenum.
It secretes digestive juices to help break down proteins and carbohydrates.
Pharynx
Pharynx: Passageway for both respiration and digestion. Play a role in deglutition or swallowing. Epiglottis covers the entrance to the trachea so that food & liquids do not enter the airway.
Esophagus
Esophagus: Long muscular tube that serves as a passageway from pharynx to stomach. The lower esophageal sphincter serves as a gateway between esophagus and stomach and relaxes during swallowing so food can enter the stomach.
Stomach
Stomach: Sac-like organ receives food from esophagus for digestion.
It secretes gastric juices that contain hydrochloric acid & digestive enzymes to break down food. The nutrients resulting in this breakdown enter the bloodstream through the walls of the stomach. Food that has been ingested is now referred to as chyme
Large intestine
Large Intestine: Tube extends from the end of the small intestine to anus. Major divisions are cecum, colon, rectum, and anus.
Role is to receive waste products of digestion and store them until they can be eliminated. Food waste enters the large intestine. Excess water is reabsorbed back into the body leaving the waste, referred to as feces. Large intestine contains gut microflora to help break down organic waste material producing gas.
Degluition
swallowing
peristalsis
Series of wave- like contraction of the smooth muscles in a single direction that move the food forward into the digestive system.
Digestion
Digestion: Process by which complex foods are broken down into nutrients in forms the body can use
Mastication
Also means chewing, breaking food down into smaller pieces and mixing it with saliva. It prepares it to be swallowed
Absorption
Absorption: Process by which completely digested nutrients are transported to cells throughout the body
Nutrients
Nutrients: Substances necessary for normal functioning of the body & include: carbohydrates, fats, proteins, vitamins, minerals, water
Metabolism
Metabolism: All of the processes involved in the body’s use of nutrients. It includes anabolism ( building up of body cells and substances from nutrients). It includes catabolism (breaking down of body cells or substances, releasing energy & CO2)
Defacation
Defecation: Evacuation or emptying of large intestine through rectum and anus.
Aphthous ulcers
Known as canker sores. Gray white pits w/ red border in mouth tissue. often associated with stress, certain type of foods or fever