Describe the Anatomy & Physiology of the Gastrointestinal System Flashcards
What is the Gastrointestinal System also referred as?
Digestive System
Where does the Digestive System start and end?
Mouth, Anus
What is the Digestive System’s function?
Break down food for absorption and distribution of nutrients to the rest of the body
Specialized regions and glands perform both ___ and ___ digestion
Mechanical and chemical (enzymatic)
The smooth muscle involved in mechanical digestion and movement of food through the Gastrointestinal System is controlled by the
Parasympathetic Nervous System
What is located along the stomach and small and large intestines and absorb digested nutrients?
Blood Vessels
Where is undigested food stored?
Rectum for elimination
Where does mechanical digestion begin?
Food ingested through the mouth
What lubricates food?
Mucus in saliva
Saliva provides ___ and ___ to initiate chemical digestion of starch and lipids
Amylase, Lipase
Food is packaged into small parcels called a ___ and swallowed (deglutition)
Bolus
As the bolus passes through the ___, the ___ closes the tracheal opening so that food does not enter the respiratory system, and the food passes into the ___
Pharynx, Epiglottis, Esophagus
What is Peristalsis?
The contractions of muscle in the esophagus
What moves the bolus through the gastric sphincter to the stomach?
Peistalsis
What does the Gastric Sphincter prevent?
Reflux of food back into the esophagus
What is the Stomach?
A sac made up of smooth muscles
Stomach muscle contractions break down the food even further into a substance called:
Chyme
What are the three main secretions of the Stomach?
Pepsinogen, Mucus, and Hydrochloric Acid
What lines the Stomach?
Mucus
What creates an acidic environment for the Stomach?
Hydrochloric Acid
What helps digest proteins in the acidic environment?
Pepsin
What is pushed into the small intestine?
Chyme
What is the first part of the Small Intestine?
Duodenum
In the duodenum, Chyme is neutralized by
Bicarbonate in pancreatic secretions
The duodenum receives ___ from the gallbladder, which helps neutralize acidic Chyme
Alkaline Bile Juices
The duodenum produce a large number of “brush border” enzymes, including:
Proteases, Lactase, and other disaccharides, and bicarbonate
Villi and Microvilli in the small intestine (largely by ileum) absorb:
Polar-digested nutrients into blood, lipids into lacteals as chylomicrons, and vitamin B12
From the small intestine, blood-carrying nutrients pass to the liver through the ___,
Hepatic portal duct
The hepatic portal duct allows liver enzymes to:
Deaminate amino acids, convert ammonia to urea, metabolize consumed toxins, and store glucose and glycogen
Digested material passes into the ___ and into the ___ or ___
Cecum, Large Intestine, Colon
The vermiform appendix projects from the ___, which is located at the junction of the ___ and ___.
Cecum, Small, Large Intestines
What is absorbed in the Small Intestine?
Water and Nutrients
What does the Large Intestine absorbs?
Remaining water and salt from digested food
What is the waste from the small intestine exposed to?
Bacterial fermentation in the colon
Vitamin K is absorbed in the:
Large Intestine
Waste accumulates in the ___ and is ejected through the ___
Rectum, Anus
What regulates many aspects of Nutrition?
Hormones
Ghrelin induces:
Hunger
Leptin causes:
The sensation of satiety
What do Hormones induce and speed up?
Induce secretions, speed up the movement of food through the small intestines
Insulin induces:
Cellular uptake of glucose
Glucagon stimulates:
The breakdown of stored glycogen
What modulates digestive action?
Hormones and Nerve Function
What are Enzymes?
Proteins produced by the body that catalyze and speed up the breakdown of food so that nutrients are available for the body
What is a chemical that aids in digestion but is not an enzyme?
Bile
What makes and releases Bile into the small intestine?
The Liver
Bile is involved in the breakdown of ___ or ___
Lipids, Fats
Organ: Mouth
What are the Enzymes and Function associated?
Enzymes: Salivary Amylase
Function: Amylase breaks down starches
Organ: Stomach
What are the Enzymes and Function associated?
Enzymes: Pepsin
Function: Break down proteins
Organ: Pancreas
What are the Enzymes and Function associated?
Enzymes: Pancreatic Amylase, Trypsin, Lipase
(Pancreas makes and released these enzymes into small intestine)
Function: Amylase breaks down starch, Trypsin breaks down protein, Lipase breaks down fat
Organ: Small Intestine
What are the Enzymes and Function associated?
Brush border enzymes (proteases, lactase)
Function: Continue to break down molecules, Carbohydrates break down into monosaccharides (simple sugars)
Organ: Large Intestine
What are the Enzymes and Function associated?
Enzymes: None
Function: None
