digestive system Flashcards
Explain how systems maintain homeostasis through negative feedback mechanisms?
It brings your body back to normal levels, for example: temperature regulation
Explain the difference between negative feedback and positive feedback mechanisms
Positive feedback mechanisms continually amplify a variable, but Negative feedback mechanisms help return the variable back to normal
The Digestive System is designed to what?
Ingest food and - while moving it through an 8m long tube - break it down chemically and mechanically into smaller components
Mechanical Digestion
The physical breakdown of food by chewing, grinding, or churning.
Chemical Digestion
The molecular breakdown of food using enzymes and digestive juices
Purpose of the teeth?
Grind up your food
What’s the purpose of your tongue?
Rolls your food into a smooth ball called a Bolus
what the Epiglottis?
A flap of tissue covering the trachea to prevent food from going into your windpipe
Salivary Amylase?
An enzyme secreted from the salivary glands in the mouth that breaks starch down into simple sugars
Mucin?
Makes the food slippery and easy to swallow
Pharynx?
Part of the pathway to both the digestive and respiratory system,
Trachea?
Path to the respiratory system
Esophagus?
Path to the digestive system
Esophagus
muscular tube through which food passes from the pharynx to the stomach
Stomach?
J-shaped sac that lies below the diaphragm toward the left side of the abdomen. This is where food stays for 2-6 hours.
What are the 2 valves that control the passage of food in and out of the stomach?
Esophageal sphincter at the entrance, pyloric sphincter at the exit.
Peristalsis?
Churns and mixed food with digestive juices (mechanical digestion)
Gastrin?
Stimulates gastric glands in the stomach wall to release gastric juices (chemical digestion)
Why does the stomach not digest itself?
Plyoric glands in the stomach secrete mucus which covers the stomach lining and prevent it from being digested, when this lining breaks, ulcers form.
The small intestine consists of three sections, what are they?
Duodenum, Jejunum, Ileum
Segmentation?
the process by which chyme sloshes back and fourth between segments of the small intestine during contractions
Bile is produced by WHAT organ?
The liver
What organ stores bile?
The gallbladder
Why isn’t bile considered and enzyme?
Because it helps digestive enzymes digest fat, but it isn’t a digestive enzyme itself.
