Summer Research Program for Science Teachers
Baruch College Campus HS, Manhattan
August 2003
~The Wonderful World of Yeast~
Intro: In this internet activity you and a partner will work together to learn the basics about yeast. This activity is an introduction that will be followed by a lab in which you observe the affects of UV radiation on yeast. All of the information is contained within the websites listed below.
If you follow all the instructions carefully you should have no difficulty finding the information. All of the answers to the questions must be WRITTEN IN YOUR WORDS. Do not copy the words directly from the websites. That is plagiarism. Worksheets in which answers are copied exactly will not be accepted. If you have any questions as you are working on this feel free to ask your partner or me. Try to answer as many of the questions as you can before visiting any of the websites. Maybe you already know more about yeast than you think! You may also look for answers in your textbook.
I. What do you know about yeast and fungi? Write down at least three things that you think of when you hear either of these words.
II. What the heck are yeast??
To find out visit this site:
http://commtechlab.msu.edu/sites/dlc-me/zoo/zbmain.html
Scroll down the page until you see “yeast.” Click on it.
a. What are yeast?
b. What kingdom of life are they classified in? _____________________
c. What are some characteristics of organisms in this kingdom?
II. What do they look like? (There is a picture of some yeast cells on the page you just visited). To see more pictures visit this site: http://www.yeastgenome.org/VL-yeast.html and click on “pictures of yeast.” You can click on any of the images to make them bigger. Label your drawing.
a. Draw a picture of yeast below and indicate the size of an average yeast next to your drawing.
Approximate size of most yeast cells: ___________
To understand how big a yeast cell really is visit:
www.cellsalive.com/howbig.htm and click on “baker’s yeast.”
III. How are they different/similar to bacteria cells?
Fill out the Venn Diagram below. Visit http://www.cellsalive.com/cells/3dcell.htm to find out more
about bacterial cells.
Yeast Similarities Bacteria
IV. How do they reproduce? Visit: http://www.phys.ksu.edu/gene/a1.html
Scroll down until you see “How do yeast grow?”
a. What is the name for the way yeast reproduce?
b. How quickly do they reproduce?
V. So what?? Why should you care about yeast? Visit: http://www.yeastgenome.org/VL-yeast.html and click on “what are yeasts?”
In what ways are yeast beneficial to humans (how have humans used them in society)? List at least two ways in which they are helpful:
a.
b.
c. Provide one way in which yeast or other fungi might be harmful: http://www.amnh.org/exhibitions/epidemic/section_04/secfour_pg_11.html
VI. Now what? –Using yeast in the lab. Visit http://www.phys.ksu.edu/gene/intro.html
and scroll down to Using Yeast to Simplify Teaching and Learning Genetics
a. Why do scientists use yeast as research subjects (instead of bacteria, fruit flies or mice)?
b. The next part of our study of yeast will involve growing them in the laboratory, observing them using the microscope and exposing them to UV radiation. Make a prediction about what you think will happen to the yeast cells when exposed to UV radiation. Explain your prediction.