Materials and
Methods
EGNE 1206
Lab 4
Materials and Methods
• Describes the experimental design, which includes:
1. controls, treatments, variables measured
2. number of replicates
3. measurements that were taken
• Appropriate level of detail-enough to recreate
experiment, not wordy
• Integrate materials and treatments
• Uses the Passive voice + Past tense + Formal Writing
Not an instructions manual or a recipe
DON'T WRITE:
• First, measure the distance between the table and floor.
Then, record the measurement…
INSTEAD:
• The distance between the table and floor was measured.
The data was recorded...
Example:
Materials and Methods
• To prepare the catecholase extract, a potato was skinned,
washed, and diced. Using a kitchen blender, 20.0 g of
diced potato and 150 ml of distilled water were blended
for approximately 2 minutes. The resulting solution was
filtered through four layers of cheese cloth and the
extract stored in a sealed, sterile container.
Breakout Groups (10 mins)
1. The petri dish was placed on the turntable. The lid was then raised slightly. An
inoculation loop was used to transfer culture to the agar surface. The turntable was
otated 90 degrees by hand. The loop was moved lightly back and forth over the
agar to spread the culture. The bacteria were then incubated at 37°C for 24 h.
2. A Spec 20 was used to measure A600 of Tubes 1, 2, and 3 immediately after
chloroplasts were added (Time 0) and every 2 min thereafter until the DCIP was
completely reduced. Tube 4's A600 was measured only at Time 0 and at the end of
the experiment.
Are these c
lear?
Appropriat
e level of
detail?
Revisions:
1. Each plate was placed on a turntable and streaked at
opposing angles with fresh bacterial culture using an
inoculating loop. The E. coli were then incubated at 37°C for
24 h.
2. A Spectronic 20 was used to measure A600 of the reaction
mixtures exposed to light intensities of 1500, 750, and 350
uE/m2 /sec, immediately after chloroplasts were added
(Time 0) and every 2 min thereafter, until the DCIP was
completely reduced. The A600 of the no-light control was
measured only at Time 0 and at the end of the experiment.
With the time remaining...
Ø Write up the materials and methods section of this experiment (~ 250 words)
NOTE: The last 5 minutes of the Experiment details the materials and what
was done. Jeremy also references the equipment used. See Excel for replicates
(raw data). Use appropriate units.
Reminder: Give enough information that someone in another class could
complete this experiment.
Format: Complete sentences/Paragraph, appropriate amount of detail, clarity.
Past tense and passive voice. Include Materials and Methods header, name and lab
day/time.
* Submit by end of day today, October 6th at 11:59 pm *
Microsoft Word - LAB REPORT GUIDE.docx
PART 1: WRITING IN THE SCIENCES ................................................................. 2
1.1 PURPOSE OF A SCIENTIFIC PAPER ...................................................................... 2
1.2 PURPOSE OF A LAB REPORT ............................................................................. 2
1.3 PLANNING YOUR REPORT ................................................................................ 3
1.4 WRITING STYLE ............................................................................................. 4
1.4.1 TONE ............................................................................................................. 4
1.4.2 VOICE ............................................................................................................ 5
1.4.3 USING THE LITERATURE ..................................................................................... 6
1.5 SCIENTIFIC VOCABULARY ................................................................................. 8
PART 2: SECTIONS OF A LAB REPORT ............................................................ 10
2.1 ORGANIZING YOUR REPORT ........................................................................... 10
2.2 TITLE ........................................................................................................ 11
2.3 ABSTRACT .................................................................................................. 12
2.3.1 DESCRIPTIVE ABSTRACTS .................................................................................. 13
2.3.2 INFORMATIVE ABSTRACTS ................................................................................ 14
2.4 INTRODUCTION ........................................................................................... 16
2.4.1 PROVIDING CONTEXT AND ESSENTIAL BACKGROUND ...................................