Yeast Lab Introduction

YEAST LAB

INTRODUCTIO

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WHAT ARE YEAST?• Eukaryotic microorganisms• Types of fungi• Unicellular organisms• Molds• Used in winemaking, baking, and

brewing• Fermentation is the process in which the yeast converts carbohydrates to carbon dioxide and alcohols

SO WHAT? WHY ARE WE TALKING ABOUT YEAST?• Yeasts are model organisms• Size•Generation time•Accessibility• Ease of care and manipulation

• We are going to use them next week in an experiment to study populations• You will work with your group to sample a population of yeast over 8 days

TODAY• Learn how to calculate population sizes

from a sample collected•Recall the sampling lab from last week• Your practice calculations sheet will be due on BLOCK

• Practice these calculations (Check for Understanding this FRIDAY)

SCIENTIFIC NOTATION……A quick way to write really, really BIG (or

really, really, small) numbers• Using powers of 10, you can create short

versions of long numbers• Proper Scientific Notation•A number must be between 1 and 10•Must be multiplied by a power of ten• Ex: 45 X 108 is NOT proper scientific notation. Why not?

EXAMPLES OF SCIENTIFIC NOTATION• 76,000,000 can be rewritten as…• 7.6 X 107

• 0.000000089 can be rewritten as…• 8.9 X 10-8

YOUR TURNUse Scientific Notation to rewrite the following

numbers:1. 347,0002. 902,000,0003. 0.0000614Answers:4. 3.47 X 105

5. 9.02 X 108

6. 6.14 X 10-5

SWITCH THESE BACK TO THEIR LONG FORMS1. 6.08 X 106

2. 1.23 X 105

3. 8.25 X 10-2 Answers4. 6,080,0005. 123,0006. 0.0825

HEMOCYTOMETER SLIDE

WE WILL BE USING THIS SLIDE IN THE LAB TO SAMPLE OUR YEAST POPULATIONS

HEMOCYTOMETER SLIDE