Digestive System Lab #9

What is the system of organs that form a continuous “tube” or “tract” which begins at the mouth and ends at the anus?

Digestive Tract or Gastrointestinal (GI) Tract

What organs are connected to the GI tract and assist in the digestive process?

Accessory Digestive organs

What are the functions of the digestive system?

1. Ingestion

2. Digestion

3. Propulsion

4. Secretion

5. Absorption

6. Elimination

What is the overall goal of the DS?

obtain nutrient molecules needs to energy production for the body

The digestive stem transfers external environmental material to the internal environment to aid in the body’s maintenance of?

water, electrolyte, glucose, and nutrient balance

What are the main fuels for the body?

carbohydrates, fats, and protein

What is the smallest form of the nutrients?

absorbable units

What is smallest unit of protein, carbohydrates, and fats?

simple sugars, fatty acids, and amino acids

What are the two processes of digestion?

mechanical and chemical digestion

What form of digestion involves the physical manipulation of the bolus of food in order to break into smaller pieces?

mechanical digestion

Where does the main area of mechanical digestion takes place?

oral cavity

Why is it important for the mouth and teeth to breka down food?

ease swallowing and increase surface area

What digestion involves using enzymes to break down the food?

chemical digestion

Where are the main areas of chemcial digestion located?

oral cavity, stomach, and small intestine

What does the oral cavity use to break down starch?

amylase

Where is protein broken down?

stomach

What breaks down protein in the stomach>

pepsin

Where are fats broken down?

small intestine

What breaks down fat in the small intestine?

lipases

What is digestion?

complex process using numerous enzymes and environments to degrade the food into its smallest absorbable units

What can secrete enzymes?

main digestive organs or accessory organs

What are the major accessory organs involved with contributing enzymes into the GI tract?

pancreas, liver, and gallbladder

What does the pancreas secrete?

digestive juices that contain enzymes to breakdown lipids, proteins, and sugars

What does the liver produce?

bile

What does bile contian?

bile salts

What do bile salts aid in?

breakdown of fat

Where is bile stored?

gallbladder up until food enters the duodenum of the small intestine

What do certain enzymes require for optimal activity and major influence on reaction rates?

pH

What pH do amylase function at?

6.8-7.0

What is optimal pH for pepsin?

2

What is optimal pH of trypsin?

7-8

What produces trypsin

pancreas

How can stress affect the stomach?

stop the production of mucous which can lead to ulcers

How do NSAIDS affect stomach acid?

Inhibit the production of the mucosal layer of the stomach