Biology Lab: Enzymes Flashcards
What is a catalyst?
A catalyst increases the rate of a reaction without being consumes
How do laundry detergents work?
Through enzymes that help break down macromolecules OR catabolic reactions that are found in stains
How can fats and oils be removed?
Surfactants that are attracted to hydrophobic molecules
What are amylases?
Enzymes that break down polysaccharides and added to remove starches
What is pepsin?
A protease found in the stomachs that breaks down protein and works at low pH.
What is trypsin?
A protease found in the small intestine and works at high pH
What is a lipase?
An enzyme that break triglycerides into glycerol and fatty acids
What is the protocol for laundry detergent?
- Grab 2 test tubes
- Test tube 1: 2 squirts of tap water
Test Tube 2: 2 squirts of detergent - 2 squirts of starch solution to each test tubes
- 3 drops of Lugol’s iodine to both test tubes
- Stir
- Observe any color changes
Do detergents contain catabolic or anabolic enzymes?
Detergents contain catabolic enzymes to breakdown molecules from hard stains
What type of enzymes breaks down polysaccharides?
Amylase breaks down polysaccharides(starches)
What is happening in the test tube to cause the color to change?
In the experimental test tube (detergent), does not have any color change when lugol’s is added which means it is a negative result. Lugol’s test polysaccharides but detergent has amylase which breaks down starch which is not detected by Lugol’s
What is a food example of a starch stain?
An example of a starch stain can be pasta that comes from fat
Why do detergents contain enzymes?
Detergents contain catabolic enzymes to break down macromolecules found in stains so they wash off easier
What is protocol for Activity of Lipase?(milk)
- Grab 2 test tubes and label
- Test tube 1: 1 squirt of milk, 10 drops of litmus, 10 drops of NaOH, and 1 squirt of water
Test Tube 2: 1 squirt of milk, 10 drops of litmus, 10 drops of NaOH, 1 squirt of lipase solution - Seal the test tubes with paraffin
- Mix
- Observe color changes
- Incubate test tubes in 37 C water bath for 1 hour
- Observe color changes
Why does you digestive system need lipase?
Lipase is needed to breakdown fats one consumes
What is the purpose of test tube 1?
Test tube 1 is the control tube that is used to compare the differences in test tube 2
What happened to test tube 2?
Lipase should breakdown from the milk which affects the ph
Would this experiment work well with skim milk?
No. This would not work well with skim milk because skim milk has fats extracted which cannot be broken down by lipase.
What is the protocol for potato catalase?
- Cut two pieces of potato
- wrap one with a wet paper towel and put in a dish to microwave for 3 minutes
- Keep the other piece uncooked
- Grab 2 test tubes one that is control (cooked) and reaction(uncooked)
- Add 4 squirts of hydrogen peroxide to each
- Cut the potato in to small pieces and place in each test tube
Which test had the most bubbles? What is the gas being produced?
Uncooked should have the most bubbles because catalase is not denatured and is functional. The gas being produced is O2
What happened to the enzyme after the potato was cooked? What caused this to occur?
The enzyme was denatured which occurred to the increase of temperature
What do you think is the optimum temperature for potato catalase?
Optima temperature is 35-37 C or body temperature
What do you think is the optimum temperature for human catalase?
Optimal temperature should be close t body temperature or 98.6 F
What factors influence enzyme activity?
Temperature, pH, cofactors/coenzymes, and inhibitors
