Digestion and Nutrition Flashcards
What are tthe 4 main processes of digestion?
Ingestion, Digestion, Absorption and Elimination
What is ingestion?
The taking in of food
What is digestion?
Mechanical and chemical breakdown of food
What is absorption?
The transport of food, salt and water molecules across the gut lining
What is elimination?
removal of undigested solid waste from the body
What is a filter feeder?
Aquatic organisms that use a body structure like a filter basket to siphon water and gather food.
What is a fluid feeder?
Fluid feeders suck or lick nutrient-rich fluids from plants or animals
What is a substrate feeder?
They live in or on their food source and eat their way through it
What is a bulk feeder?
They ingest large pieces of food
Where does Mechanical Digestion begin?
In the mouth. The teeth and tongue grasp, masticate and manipulate food that is about to be swallowed.
Why is Mechanical Digestion important?
Because it increases the surface area of the good for digestion by enzymes and makes it easier to swallow.
What is Peristalsis?
wave length muscle contractions that move food to different processing stations in the digestive tract
Movement of food after swallowing is..
Involuntary and under the control of the autonomic nervous system.
What is the esophageal sphincter?
A ring like muscle that closes the passage between the stomach and esophagus.
What does the esophageal sphincter do?
As food approaches the closed sphincter, it relaxes and allow the food to pass through into the stomach.
What is GERD and what causes it?
GERD is gastroesophageal Reflux disorder and is caused when the ES doesn’t close properly.
What is the three mechanical tasks of the stomach?
Storing swallowed food, mix food/liquid and digestive juices and empty its contents.
What are some factors that affect emptying of the stomach?
Several factors affect emptying of the stomach like the kind of food and the amount required to break down the food. Example, carbs spend the least amount of time in the stomach while protein stays longer and fats the longest.
What are the four main areas of the stomach?
The cardia, fundus, body and pylorus.
What separates the stomach from the duodenum?
The pyloric sphincter
What happens to the wall of the stomach when it’s empty?
It is folded into rugae.
What is food called when it goes from the stomach to the small intestine?
Chyme
What are the movements along the large intestine?
Segmentation, peristalsis and mass movements
What occurs during segmentation?
Alternate sections of muscle contract and move feces back and forth, causing mixing but does not propel fecal matter along the colon
