The Characteristics of Model Organisms

1
The Characteristics of Model Organisms

• Lab Manual2b

2
Plan for Lab

• Tues. (1 hr early)Duffy will start yeast broth
• TuesdayFinish Lecture, Parts I, II III
• WednesdayFIRE, Part IV
• Thursdayrepeat 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 Kingdomrats, mice (lots of offspring is a
  )
• BacteriaEscherichia coli (E. coli)-prokaryotes
• FungalAspergillus (mold)--eukaryotes
• YeastSaccharomyces cerevisiae

5
Lab Write-up

• Purpose
• Materials
• Safety Precautions
• Procedures
• Data Collection Analysis (table 2.3add 8C,
  only 2 trials to average)
• Conclusion (aka Data Analysis)
• REE-results, evidence, explanation
• PEpossible error
• PApractical 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 bakers 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-labPlate Pouring

• Pour LB agar base plates (Luria-Bertani )
• E. Coli plateuse the LB agar with sterile
  technique, use a 10ml pipette to transfer 10ml
  into a sterile plate
• Yeast plateuse 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
Each group does 1 plate of each organism at their
assigned Temperaturewrap in foil for dark

• room
• room
• 30C
• 30C
• 37C
• 37C
• 42C
• 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 platewill 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 IVData 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)