Hello ChElGluGrav! Welcome to the third quarter! 😀
- Please work on the pair SW mindfully.
- Make sure you understand each answer you write on your worksheet.
- Submit your worksheets at the end of the period for grading.
- Announcements for next week:
- Submit your Biomolecules pre-lab, data table, and answers to questions (with APA citations and list of references) during the second meeting next week.
- We will have a laboratory activity on enzymes during the first two meetings of next week (Nov11-13) and we will meet at SHB109.
- Groupings will be the same as in the biomolecules activity.
- Please download the procedure for the lab activity here. Instead of a pre-lab, please do Part II, Steps 1-4 before coming to class on the first meeting next week.
- A short quiz on enzymes will be given on the second meeting next week before the second part of the lab activity.
Overview: Enzymes and activation energy
View Part I of the animation at http://www.sumanasinc.com/webcontent/animations/content/enzymes/enzymes.html , click on “show narrative” and answer the questions that follow.
- What is the activation energy (EA) of a reaction?
- How do enzymes affect the EA of a reaction?
Enzyme structure and function
View http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter2/animation__how_enzymes_work.html, click on “text” and answer the next question:
- On a molecular level, how does the shape of an enzyme enable it to perform its function? Use all the following terms in your answer: active site, substrate, enzyme-substrate complex, and product.
View http://www.wiley.com/college/boyer/0470003790/animations/enzyme_binding/enzyme_binding.htm, click on “Binding Models” and answer the next question:
- What is the difference between Emil Fisher’s lock-and-key model and Daniel Koshland’s induced fit model? What is the current model like?
Factors that affect enzyme action
- Knowing what you know about the nature of enzymes, predict how the following factors affect enzyme function:
Factors Effect on reaction rate if factor is reduced/decreased Effect on reaction rate if factor is raised/increased Brief explanation as to why these factors affect enzyme function and reaction rates in that way
- a. Enzyme concentration
- b. Substrate concentration
- c. Inhibitor concentration
- d. Temperature
- e. Size of container
- f. pH
- View http://moleculesoflife2010.wikispaces.com/file/view/Enzyme+Model.swf and test your hypotheses using controlled experiments (you may need to use a timer to assess reaction rates). Do your results agree with your predictions? Write a short summary of your results below.
View http://programs.northlandcollege.edu/biology/Biology1111/animations/enzyme.html and click on “Enzyme Inhibitors” and answer the question below.
- What is the difference between a competitive and noncompetitive inhibitor?
View http://programs.northlandcollege.edu/biology/Biology1111/animations/enzyme.html and click on “Allosteric Enzymes” and answer the question below.
- What are allosteric enzymes?
- We learned in Bio2 that the haemoglobin molecule exhibits cooperativity. What happens to the structure of haemoglobin once oxygen binds to a subunit?
View http://programs.northlandcollege.edu/biology/Biology1111/animations/enzyme.html and click on “Feedback Inhibition” and answer the question below.
- Feedback inhibition regulates metabolic pathways that use more than one enzyme. How does feedback inhibition work?