Digestive System

taylormaloney's version from 2016-04-10 04:03

Section 1

Question Answer
What are the first three basic digestive processes?Ingestion, Secretion, and Mixing/Propulsion.
What are the final three basic digestive processes?Digestion, Absorption, and Defecation.
Define the first step in digestion.Ingestion- Taking food and liquids into mouth.
What is the second step in digestion?Secretion- Water/Acid/Buffers/Enzymes secretied into lumen by cells in GI Tract.
What is the third step in digestion?Propulsion/Mixing. - Moves food along- combines secretions and food with alternating contraction/relaxing of SMT.
What is the fourth step in digestion?Digestion itself- chemical and mechanical processes break down food.
What is the fifth step in digestion?Absorption- Nutrients and digested end products absorbed into blood/lymph.
What is the last step in digestion?Defecation- elimination of wastes, indigestible materials, bacteria, etc as feces.

Section 2

Question Answer
Describe what takes place during ingestion.Food/Liquid enter mouth-Teeth cut, tear, and pulverize food.
Describe what takes place during Secretion.Water/Acid/Buffers/Enzymes secreted into lumen by cells within GI tract.
Secretion activates what process?Chemical Digestion- starch is broken down by Salivary Amylase, Lingual Lipase is secreted to be activated later.
What is Secreted in the Stomach?HCl- Acid to kill microbes and activate enzymes. Pepsin- protein digestion enzyme. Mucus- Lubrication and protection of tissue.
What takes place during Mixing/Propulsion?Bolus is moved along digestive system via contraction/relaxation of SMT.
What is the relationship between Propulsion and Mechanical Digestion?The propulsion and mm contraction causes bolus to combine with secretions. Mixing waves create chyme.
Define Deglutition.Swallowing- Coordinated activity of tongue, soft palate, pharynx, and esophagus.
What are the two phases of Deglutition?Buccal- food forced into oropharynx. and Pharyngeal-Esophageal- food moved through pharynx to esophagus.
Is Deglutition voluntary or involuntary?Buccal Phase- voluntary. Pharyngeal- Non Voluntary.
What is the Rugae in the Stomach?Longitudinal folds that allow stomach to extend.
Why are these necessary?Stomach must expand when full, used as storage for Chyme.
What is Chyme?Food mixes with gastric juices.

Section 3

Question Answer
How does Chyme move into the Small Intestine?Mixing/Propulsion forces small amounts of chyme into duodenum.
How long does it take for Stomach to fully empty?Liquids/Carbohydrate Chyme moves quickly. Fat and Proteins take longer 4 + Hours.
How does exercise relate to digestion?Chyme digested faster during low intensity exercise than times of rest. High intensity exercise slows digestion.
What is the major organ related to digestion/absorption?Small Intestine.
What are the three main regions of the small intestine?Duodenum, Jejunum, and Ileum.
What does Duodenum mean?Width of twelve fingers.
What are it's more important features?Duodenal Papilla and Sphincter of Oddi.
What do these receive?Bile from gallbladder/liver, and Pancreatic Enzymes.
What takes place in Jejunum?Absorption of nutrients digested in duodenum.
What takes place in Ileum?Absorption of vitamins, B12, bile salts, and products not absorbed by jejunum.
Where does the Ileum end?Gives way to the Long Intestine via the Ileocecal Sphincter.
What are Villi?Finger like projections from intestinal lining.
What are their purpose?Increases surface area for digestion/absorption.
What does the Small Intestine do with carbohydrates/lipids/proteins?Finishes digestion- completes virtually all nutrient absorption.

Section 4

Question Answer
In the human body where is the large intestine situated?It 'Frames' the Small Intestine.
What are it's main functions?Stores and Concentrates undigested materials.
How does it perform the concentration?It absorbs water and salt to prepare it for excretion
Does digestion take place in the Large Intestine?No- no digestion takes place past the small intestine.
What is the vermiform appendix?A safehouse for beneficial bacteria.
What is absorbed in the Large Intestine?Vitamins, Water, and Electrolytes.
What is the major function of the Long Intestine?Propulsion of fecal matter towards anus.

Section 5

Question Answer
What is the relationship between the liver and the digestive system?It produces bile.
What else does the liver do?Stores glycogen and eliminates wastes and trace metals from the body.
The liver is also the ______ gland in the body.Heaviest.
What is bile?A yellow-green alkaline solution containing bile salts, bile pigments, cholesterol, and electrolytes.
What are bile salts?They emusify fat to enhance digestion, absorption of fatty acids, and fat-soluble vitamins.

Section 6

Question Answer
What is the relationship between the Gallbladder and the Digestive System?It stores bile not immediately needed for digestion.
What does the Gallbladder do after meals?It's muscular walls contract, squeezing bile out through the common bile duct into the small intestine.
What are Gallstones?Crystalization of cholesterol- causes when insufficient bile salts/excessive cholesterol.
What is a Cholecystectomy?The removal of gallbladder.

Section 7

Question Answer
Where is the Pancreas situated in the human body?Lies deep to the greater curvature of the stomach.
What does it do?Secretes juices that aid in digestion and absorption of nutrients.
What is the pH level of Pancreatic juice?7.1-8.2
Why is the pH level important?The juice acts to buffer the gastric juices, creating a proper environment inside the small intestine.