UTPA STEM/CBI Courses/Nutrition/Enzymes

Course Title: Nutrition; General Biology I

Lecture Topic: Enzymes, Organic and biochemistry

Instructor: Associate Professor Diane Teter

Institution: South Texas College, McAllen, Texas

Backwards Design

Course Objectives

• Primary Objectives- By the next class period students will be able to:
  • Explain and give an example of catalysis
  • Understand/apply use of enzymes for catalysis
  • Distinguish between proteins and enzymes and their interactions
  • Understand denaturation (shape alteration) of proteins by catalysts

• Sub Objectives- The objectives will require that students be able to:
  • Define hydrolysis and how it is used in food preparation
  • How to alter an enzyme catalyst

• Difficulties- Students may have difficulty:
  • Understanding the relation of enzyme to a substrate
  • Grasping the relation of an enzyme and its enzyme-substrate complex
  • Relating of enzyme to its products

• Real-World Contexts- There are many ways that students can use this material in the real-world, such as:
  • Food preparation in nutrition
  • Inorganic and biochemistry experiments

Model of Knowledge

• Concept Map
• Enzymes in pineapple products that affect gelatin
  • Sundried pineapple
  • Fresh pineapple
  • Fresh pineapple denatured by heat
  • Canned pineapple

• Content Priorities
  • Enduring Understanding
  • What an enzyme is and does
  • What catabolism means in relation to enzymes
  • How enzymes can be used in culinary arts
  • Important to Do and Know
    • Experimental design
    • What is hydrolysis and how it can be used in culinary arts
    • Now proteins can be denatured
  • Worth Being Familiar with
    • Gels
    • Acids
    • Mixing together of both the above for food preparation

Assessment of Learning

• Formative Assessment
  • In Class (groups)
    • Perform experiment
    • Analysis of experimental results or data
  • Homework (individual)
    • Report on experiment
    • Research of other enzymes use in cooking examples
    • Research of denaturation of proteins and how relates to cooling/nutrition and examples
• Summative Assessment
  • Test on enzymes,
• their effects
• inhibition
• enzyme substrates
• products
  • A food example of enzymes in food preparation/cooking or wellness

Legacy Cycle

OBJECTIVE

By the next class period, students will be able to:

• Understand and explain what a catalyst is and give examples
• Distinguish between proteins and enzymes and their interactions.
• Understand and explain denaturation of proteins by catalysts.

The objectives will require that students be able to:

• Design and conduct an experiment with its analysis
• Write up a lab report and discuss the consequences of the lab in a real world situation

THE CHALLENGE

Why did my Jello not gel? It’s Thanksgiving and you were to make and bring a gelatin dessert with pineapple chunks to the dinner. You had no problem choosing the flavor of the gelatin, but you had problems choosing the type of pineapple (canned, fresh, cooked fresh, or dried) to use for your recipe. You chose fresh pineapple chunks, so why didn’t the Jello gel?

GENERATE IDEAS

• Brainstorming in groups of 3-4
• Researching online
• Collaborate with an expert in culinary arts, biology or chemistry

MULTIPLE PERSPECTIVES

• Study and review of enzymes, catalysts, proteins, hydrolysis, and gelatin
• Nutrition or Culinary Arts Instructor as speaker
• Virtual Lab on Biology text publisher’s site
• How enzymes work in the human body in digestion and give examples
• Nutritional value of pineapple with respect to its type of preservation

RESEARCH & REVISE

• Lecture
• Lab experiment on catalysis using enzymes in pineapple (types of preparation)

TEST YOUR METTLE

• Discussion/collaboration for laboratory report
• Written test
• pre-test
• post-test

GO PUBLIC

• Presentation to class/teacher/group
• Lab report
• Discussion questions for online course
• Bring your gelatin dessert to class for tasting

Pre-Lesson Quiz

1. In the reaction A + B → C + D, the reactant(s) is/are:

• a. Only A
• b. A and B
• c. Only D
• d. C + D

2. Enzymes ______ .

• a. Slow down chemical reactions
• b. Increase the energy of activation
• c. Bring together specific molecules and causes them to react with each other
• d. All of these

3. The speed of a reaction that involves an enzymes increases as____ .

• a. Optimal temperature decreases
• b. pH becomes less than optimal
• c. substrate concentration increases
• d. all of these

4. Denaturation _____.

• a. Changes the shape of the enzyme
• b. Prevents the enzyme from binding with its substrate molecules efficiently
• c. Occurs at temperatures above a certain point
• d. All of these

5. A very high fever (105 degrees F) is dangerous because enzymes can become ________.

• a. Ionized
• b. Denatured
• c. More structured

Test Your Mettle Quiz

1. Which statement describes the currently accepted theory of how an enzyme and its substrate fit together?

• a. As the product is released, the enzyme breaks down
• b. The enzyme is like a key that fits into the substrate, which is like a lock
• c. The active site is permanently changed by its interaction with the substrate
• d. As the substrate binds to the enzyme, the shape of the active site changes to accommodate the reaction

2. Which statement is NOT true about the effects of various conditions on the activity of an enzyme?

• a. Higher temperatures generally increase the activity of an enzyme up to a point.
• b. Above a certain range of temperatures, the protein of an enzyme is denatured.
• c. A change in pH can cause an enzyme to be inactivated.
• d. An enzyme’s activity is generally reduced by an increase in substrate concentration.
• e. When sufficient substrate is available, the active site will nearly always be occupied.

3. Which statement is NOT true about enzyme inhibition?

• a. In competitive inhibition, the inhibitor binds to the active site of the enzyme
• b. In noncompetitive inhibition, the inhibitor binds to the allosteric site of the substrate
• c. In irreversible inhibition, a poison binds to the enzyme so that it can never work again
• d. Most inhibitors act in a reversible fashion
• e. All of the statements are true

4. A coenzyme is

• a. An ionic cofactor that interacts with an enzyme to allow it to work
• b. A protein cofactor that interacts with an enzyme to allow it to work
• c. A non-protein organic cofactor that interacts with an enzyme to allow it to work
• d. An ionic cofactor that interacts with an enzyme to inhibit it
• e. A protein cofactor that interacts with an enzyme to inhibit it

5. Energy coupling of endergonic and exergonic reactions within cells

• a. Permit biological reactions to proceed at temperatures consistent with life
• b. Uses heat released by one reaction to fuel the other reaction
• c. Utilizes ATP to carry energy between the exergonic and endergonic reactions
• d. All of the choices are correct

6. Of the following, which process will not denature a protein?

• a. Heating to temperatures above 100 C
• b. Addition of strong acids or strong bases
• c. Phosphorylation
• d. Addition of distilled water

7. While eating a container of yogurt, you have to leave, so you store the yogurt in the refrigerator. A day later you return and find the surface of the yogurt is no longer smooth but has broken into several liquefied product. You correctly guess that enzymes from your saliva, via the spoon, have continued digesting the yogurt in your absence. What will happen over time?

• a. The reaction will soon stop because the amount of saliva is small, and you would have to add more saliva to continue the degradation
• b. The reaction will continue, since the enzyme is not consumed by the reaction
• c. The reaction will continue until half is digested and then stop because the reaction between substrate and product will be balanced
• d. Absolutely no degradation of the yogurt will occur naturally unless in the presence of this enzyme

8. If there are twelve different intermediate products produced in the stages for production of a molecule in a cell, we can expect that there

• a. Is one enzyme that carries this process through to the end product
• b. Is one enzyme for degradation and another enzyme for synthesis
• c. May not be any enzymes involved if this is a natural cell product
• d. Must be twelve different raw materials combined in the cell by one enzyme
• e. Are about twelve enzymes, at least one responsible for each step in the metabolic pathway

9. In order to roll a rock down a hillside, you must first push it up out of the hole in which it rests. Pushing the rock is analogous to the energy of activation of a chemical

• a. True
• b. False

10. An enzyme is a globular protein that inhibits the formation of chemical bonds within the enzyme’s substrate(s).

• a. True
• b. False

11. If a change in pH alters an allosteric site where an inhibitor binds, but doesn’t change the active site for the intended substrate, it would be possible for an enzymatically controlled reaction to occur as normal.

• a. True
• b. False

12. In the reaction A + B → C + D, the reactant(s) is/are:

• e. Only A
• f. A and B
• g. Only D
• h. C + D

13. Enzymes ______

• e. Slow down chemical reactions
• f. Increase the energy of activation
• g. Bring together specific molecules and causes them to react with each other
• h. All of these

14. The speed of a reaction that involves an enzymes increases as____

• e. Optimal temperature decreases
• f. pH becomes less than optimal
• g. substrate concentration increases
• h. all of these

15. Denaturation _____.

• e. Changes the shape of the enzyme
• f. Prevents the enzyme from binding with its substrate molecules efficiently
• g. Occurs at temperatures above a certain point
• h. All of these

16. A very high fever (105 degrees F) is dangerous because enzymes can become ________.

• d. Ionized
• e. Denatured
• f. More structured