Summer Research Program for Science Teachers
Baruch College Campus HS, Manhattan
August 2003
What are Yeast?
Objectives:
· Students (Ss) will use the internet to learn about yeast
· Ss will understand that yeast are living things
· Ss will learn the basics of yeast cells, their reproductive cycles, and their usefulness as a research tool
· Ss will observe living yeast cells
· Ss will conduct an experiment in which yeast cells are exposed to UV radiation
· Ss will make connections to humans and UV radiation as a cause of skin cancer
National Standards:
· Standards C, E, F, G,
Materials:
· Yeast internet worksheet
· Computer lab with internet access
· Microscopes, slides, yeast cells
Lesson Outline:
1. Do-Now: What are yeast? What are fungi? List at least three things you know about yeast and fungi. (3 minutes)
2. Discuss do-now. (5minutes) Teacher (T) may wish to write responses on a piece of chart paper which is divided into two sections. One section can be devoted to students’ responses prior to the internet activity and the other section can be devoted to students’ knowledge after the activity.
3. T explains that the class will using yeast in an upcoming experiment and that prior to doing the experiment it is necessary to learn the basics about yeast.
4. T distributes worksheets. T can distribute these at the beginning of class and have students answer the do now question directly on the sheet (question 1).
5. T divides students into pairs assigns them each to a computer. T instructs Ss to follow directions on sheet.
6. **T allows students to work for an entire period on the activity. (45-50 minutes)
7. Discuss answers to questions as a class or in small groups. Any unanswered questions can be asked at the end of the activity or at the beginning of the next class. Students should also be encouraged to generate a list of questions on things they still don’t understand.
**The internet activity is designed using numerous websites. It was a challenge to find a comprehensive and user (student) friendly website on all the aspects of yeast asked about in the activity. Most websites were designed for a higher level scientific audience. It might be difficult and time consuming to type in each website trying to find information. If possible, the teacher is encouraged to create a webpage (a class website perhaps?) with all of the sites already listed as links so students only need to click on them. This will also ensure that student are able complete the activity in the time allotted and with minimal frustration.
Part II: Preparing Wet Mounts of Yeast cells
Use standard wet mount technique to examine living yeast cells. Yeast cultures on YED/YEPD (rich agarose medium) can be grown 3 days in advance or yeast can also be cultured in liquid medium overnight (transferred from agarose medium to liquid YEPD or water).
Part III: How does UV Radiation affect the growth of yeast cells?
This is currently under construction and will likely be next summer’s lesson plan. Check back in a year or contact me and I will be happy to give you a rough copy. I hope to try this out in my own lab as well as with my students prior to submission (want to make sure it works and iron out any kinks!)