The Effect of Alcohol on Lumbriculus variegates
By: Martha Vallejo and Jasmyn Smith
Introduction: This experiment that we have
conducted was created to measure the affect
of a said toxin on Lumbriculus variegates on
their pulse rate. Lumbriculus variegates, also
referred to as California blackworm. The
worms have transparent skin, which makes it
easier to analyze the pulse rate. In this
experiment, the pulse rates were analyzed
over a duration of time, and then compared.
Alcohol is described as a depressant drug; it
elevates blood levels and significantly affects
the central nervous system of an organism.
The molecular formula for alcohol, or Ethanol
is CH3CH2OH. In this experiment, we used
40% ethanol alcohol in our solution, making
our solution a 1mM solution.
Hypothesis: If the worms are put in a alcohol
solution then they will have a slower pulse
rate than the worms in the distilled water.
Procedure:
Step 1: Label cups (distilled, alcohol, distilled
recovery, alcohol recovery) and fill with 4mL of
said solution.
Step 2: Place 10 worms in the alcohol for 15
minutes and then place each worm on the well
slide, using microscope 10x, count the pulse
rate for 30 seconds in the midsection of the
worm. (Repeat for each worm).
Step 3: Record data (double for a minute count)
and place worm in recovery cup.
Step 4: Repeat steps to measure pulse rate
with worms in distilled water. Remove each to
recovery cup.
Worm
1
2
3
4
5
6
7
8
9
10
Distilled Pulse Alcohol Pulse
20
Dead
20
4
22
6
20
28
24
6
22
8
24
6
20
10
20
Dead
20
6
21.2
7.4
20
6
Independent Variable: Alcohol Solution.
Dependent Variable: The difference in pulse
rate.
Control Setup: Distilled water.
Mean
Constants: Amount of water, temperature,
Median
microscope, and time.
References:
Materials: 20 worms, 1mM alcohol, 1mM Www.wikipedia.org/wiki/Ethonal#Name
distilled water, Microscope, well slides, cover Www.newworldencyclopedia.org
slides, 4 cups, and dropper.
Www.ableweb.org/volumes/vol27/07_Bohrer.pdf
Results: The average pulse rate for the worms in
distilled water is 21.2. We found that the average
pulse rate for the worms in the alcohol solution is 7.4.
Conclusion: After analyzing the data, we found that
our hypothesis does in fact support our data. The
data shows us that the worms reacted to the
depressant just as we thought. A common pulse rate
for worms in distilled water was 20. A common pulse
rate for worms in the alcohol solution was between 4
and 8. We also had 2 worms within the alcohol
solution die. While calculating the pulse rates for
worms in distilled water, they were very active, which
could have caused inaccuracies. To solve the
inaccuracies due to their movement, smaller well
slides were made. Also, keeping them out of the light
source from the microscope may calm them down. In
order to expand our knowledge on the effects of
alcohol on Lumbriculus variegates, we can increase
the number of trials. Other chemicals could be tested
on the worms as well.