Photosynthesis and Respiration: Are They Similar?

Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To compare and contrast two challenging topics: photosynthesis and cell respiration

– To appreciate that comparing and contrasting topics is an important study tool

– To promote discussion and questions from students about where they are confused

Activity Description: After students have already had lectures on cell respiration and photosynthesis, they are asked to compare and contrast these topics. This could be a very open-ended activity or can be done with a quick worksheet.

Time Needed: Activity should take about 15 minutes but could go on longer with much discussion and review

Materials Needed: Copies of the worksheet below

Activity Instructions: After students have learned about both processes, allow students time to compare and contrast photosynthesis and cell respiration. Students often get confused by the similarities of the topics but can’t always pinpoint where they are similar or different. This activity will open up discussion to find out where students are having trouble.

Worksheet: Photosynthesis and Cellular Respiration Worksheet

Students, Design Your Own Enzyme-Catalyzed Reaction

Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To practice using terms related to enzyme-catalyzed reactions

– To address a misconception that enzymes are depleted after a reaction

Activity Description: Students are given a list of words and instructions to design their own enzyme-mediated reaction. Students work in small groups to design and then demonstrate their idea to the class (students can use simple props). The whole class can decide if the demonstration is designed well to illustrate understanding. The activity can work in a small class or a large class in which only a few groups get to demonstrate. You may also choose to simply demonstrate your own example asking students to come up with ideas as you prompt them.

Time Needed: Activity may take 40 minutes (if students do group work outside of class) and may take much longer if group time is given during class

Materials Needed: Variable depending on students

Activity Instructions:

Tell students that they will design an enzyme-catalyzed reaction (could be dehydration synthesis, hydrolysis, functional group transfer, etc.) that shows their understanding of the words/ideas below. The materials students have available can be props available in a classroom, such as classmates, paper, pens, etc. You may suggest that students work outside of the class and plan ahead to bring simple props with them. Groups will demonstrate their ideas to the class. You may want to have a panel of student judges (American Idol style).

Ideas that students can demonstrate:

A. active site

B. substrate

C. product

D. enzymes are used over and over.

E. enzymes can be inhibited at their active site or their allosteric site.

F. enzyme activity is affected by environmental conditions.

Example: I place a bowl of wrapped candies on my table. I tell them that I am unwrappase. The substrate is wrapped candy and the product is unwrapped candy. My hands are the active site. A single me can unwrap many candies (enzymes are used over and over and are unchanged). The rate of me producing unwrapped candies would slow down if pistachio nuts were mixed into my bowl because the pistachio nuts would temporarily bind to my active site. Pistachios would be competitive inhibitors. If a scarf was tied around my elbows to connect them behind my back, the active site would be altered because my hands would open up and I would have trouble holding the candy. The scarf would be an allosteric inhibitor. Ideally, I work best at room temperature. If the heat was turned way up or way down my activity might be slowed by these environmental conditions, and I might be cranky and produce less product.

Using Diabetes as the Story to Discuss the Secretory Pathway of Proteins

Written by Kelly A. Hogan, University of North Carolina at Chapel Hill

Learning Outcomes:

– To use insulin as an example secretory protein

– To examine an analogy that the cell is a protein factory analogous to a manufacturing factory

– To learn about an important disease students may know little about

Activity Description: Students act out an interpreted case study and discuss answers to the questions. Lecture or animations may be interspersed in the discussion.

Time Needed: Approximately 50 minutes

Materials Needed: Copies of the case study and questions, 3 x 5 index cards

Activity Instructions: Choose 6 students to play the roles. Intersperse lecture, BioFlix animations, and discussion as needed. I always play the role ofLena, so that I can still play a “teaching role” and pull up animations while I say my lines.

OPTIONAL: The animation that could be shown to the class is located at:

For question 8, I have my students write their answers on 3 x 5 index cards. I ask them to swap cards several times with classmates. When I ask for people to read from their cards, I get a much better response. We then discuss whether the analogy is a good one or not.

Worksheet: Diabetes Case Study and Role Play Worksheet