Exam 3- Digestive System Flashcards
What are the three groups of Macronutrients? Name a food that they can be found in.
Lipids (butter) Proteins (chicken) and Carbohydrates (pasta)
Discuss three enzymes and give the following information:
- pH Levels
- What does it break down
- Where is it produced
- Where does it work
Lipase: is produced in the pancreas. It breaks the polymer lipid down into fatty acids and glycerin which can be absorbed in the small intestine. This process occurs in the small intestine. It has a basic pH- 8.
Amylase: is produced in the salivary glands and pancreas. Salivary amylase breaks the starch down into smaller polysaccharides. The pancreatic amylase breaks the polysaccharides down into disaccharides. The amylase has a neutral pH of 6.
Pepsin: is produced in the stomach activated by the HCl in the stomach. It breaks down the polypeptide chain into singular amino acid molecules monopeptide. This process occurs in the stomach. Pepsin has an acidic pH of: 1-2.
What is an enzyme?
A biological catalyst (speeds up reactions)
What is Digestion?
Digestion- breaking down large food molecules into smaller ones that can be absorbed
Explain the two different types of digestion.
Mechanical Digestion- Breakdown of the food by chewing.
Chemical- breakdown of the food by enzymes
Explain how the ‘better milk for cats’ represented the human digestive system
The milk represents the food that travels through the digestive system. The beads represent the beads on the GI Tract. As the milk went through the tube more times it was broken down into glucose and galactose as foods are broken down when they go through the GI tract.
Where does most absorption occur?
Small Intestine
Where is water absorbed?
Large Intestine
Explain what occurs during diarrhea. What is the treatment?
Diarrhea occurs when too little water is reabsorbed and the feces are very liquid. The treatment for diarrhea is rehydration salts.
What happens to the nutrients once they have been absorbed?
USING PROTEIN DIGESTION AS AN EXAMPLE
When a protein is ingested it is the pepsin enzyme that breaks down the protein. The pepsin which has a pH of 1-2 breaks down the polypeptide into a monopeptide so that it can be absorbed into the capillary network of the villi. The amino acids are then rearranged by a different enzyme. The amino acids are then sent off to the cells. The enzyme can build a chain of varying lengths and varying orders. They have to be in the order required to make the proteins we need.
Where are the feces stored ready to be excreted?
Colon
What food helps with bowel movement? Explain.
Fiber helps with bowel movement because it cannot be broken down, absorbed or digested, therefore it travels straight through the GI tract which cause bowel movements.
Which food is lactose found in? Where is it digested and by what?
Lactose is found in diary products. It is digested in the small intestine by lactase.
Describe how we test for starch
To test starch we use Iodine Solution which is brown. If starch is not present the solution will remain brown and if starch is in fact present the solution will turn blue or blue black.
Describe the two ways we test for glucose.
To test for glucose we use Benedicts Solution. The food is crushed with a pestle and mortar and placed into a tube. The blue solution is then placed onto the food with a dropper. The solution will not change color if glucose is present unless it is heated. Once the test tube is heated the solution will brick red/ orange if glucose is present and will remain blue if it is not. Typically, we use pH strips to test for glucose in a liquid. The strip will change color based on level of glucose present in the liquid.
