1. The Characteristics of Model Organisms
Lab Manual—2b

2. Plan for Lab Tues. (1 hr early)—Duffy will start yeast broth
Tuesday—Finish Lecture, Parts I, II & III
Wednesday—FIRE, Part IV
Thursday—repeat Part IV/start write-up

3. Model Organisms
Relatively easy to grow and maintain in a restricted space
Relatively easy to provide necessary nutrients for growth
Relatively short generation time (birthreproductionbirth)
Relatively well understood growth and development
Closely resemble others organisms or systems

4. Examples Animal Kingdom—rats, mice (lots of offspring is a +)
Bacteria—Escherichia coli (E. coli)-prokaryotes
Fungal—Aspergillus (mold)--eukaryotes
Yeast—Saccharomyces cerevisiae

5. Lab Write-up Purpose Materials Safety Precautions Procedures
Data Collection & Analysis (table 2.3—add 8C, only 2 trials to average)
Conclusion (aka Data Analysis)
REE-results, evidence, explanation
PE—possible error
PA—practical applications
Thinking Like a Biotechnician

6. Background of Purpose To grow and study an organism in a
laboratory, one should know the
environmental preferences of the species.
Maintaining an organism at less than optimal
light intensity, temperature, or oxygen level,
from example, may put the organism under
stress, possibly affecting its growth or other
processes.

7. Purpose
What are the temperature preferences shown by three model organisms (E. coli, Aspergillus niger and baker’s yeast) grown in a biotechnology lab?

8. Prep. For Lab 2B Month Prior
Check supplies: bleach, petri dishes, LB base, inoculating loops, 3 incubators, yeast, glucose, foil
Order: E. coli, Aspergillus, Potato plates
Week Prior
Perez will prepare LB agar & broth
Pour plate (2 per group20)
Set incubators at 30, 37 and 42 C
Scalpels from other room
1 day prior
make bacteria culture

9. Pre-lab—Plate Pouring
Pour LB agar base plates (Luria-Bertani )
E. Coli plate—use the LB agar with sterile technique, use a 10ml pipette to transfer 10ml into a sterile plate
Yeast plate—use the LB* agar, sterile technique, transfer 10ml using a pippet
*we are not using Malt extract agar because we do not have it, but LB agar should have enough nutrients to grow yeast

10. 8C (instead of the suggested 4C)—please do 2 sets
Each group does 1 plate of each organism at their assigned Temperature—wrap in foil for dark
room
30C
37C
42C
8C (instead of the suggested 4C)—please do 2 sets

11. Part I Tips Label the bottom Inoculating loop
Triple Z streaking method
Close lids with tape
Make sure to use plate with LB agar

12. Part II Tips
Each group gets one plate instead of a tube of potato dextrose agar
We are using a potato dextrose agar plate NOT tube
Cut aspergillus from stock plate—will be in the hood
Put the aspergillus (fungi) on the plate fungi side down to the agar and close the lid

13. Part III Tips Label the bottom Inoculating loop
Triple Z streaking method
Close lids with tape
Make sure to use plate with LB agar

14. Part IV—Data Collection & Analysis
Make sure to come in at FIRE on Wednesday to do a table like 2.3 (add space for 8C)
We will repeat the table again on Friday in class
This will provide us with more information of what happens over time as well as temperature
The growth is exponential, but when nutrients run out, they go into the death phrase (smelly!), we want to try to catch them at their peak
Use results from all the groups posted on the internet for you data

15. Tutorials Media Prep. (13) LB Agar and Broth (14)
Sterile technique (15)
Pouring Plates (16)
Starting a Broth (18)
Streak Colonies (17)