1. Blackworms in Plain and Stimulated Water
The Effects of a Stimulant on the Pulse Rate of the Lumbriculus variegatus
Israel Florentino and Raven White, Albion High School GCC Bio 100
Introduction:
The Lumbriculus variegatus (also known as the California Blackworm) are an invertebrate that are bilaterally symmetrical. The L. variegatus lives on the edges of ponds, lakes, and marshes. They breath by stretching their tail vertically to form a 90 degree angle and break the water surface tension. You can tell the anterior from the posterior by, the anterior is more darkly pigmented, wider, and more maneuverable than the posterior.
Procedure:
Set up microscope.
Place Blackworm from controlled group into well slide.
Observe under microscope pulse rate for 1 min. intervals for ten trials.
Record in data table.
Repeat steps 1-3 for the worm from experimental group.
Create a graph
Figure out results between the worms’ pulse rates.
Write Conclusion
Hypothesis:
If a black worm is placed into a solution with a stimulant water then the pulse rate will be faster than pulse rate of a worm in solution of plain water.
Independent Variable:Stimulant Solution.
Dependent Variable Worm’s Pulse Rate.
Control Setup: Worm’s Pulse Rate in Normal water
Constants: The temperature of the water and how long the worm is in the solution.
Results:
After doing the calculations, the mean pulse rate of the worm only in spring water was 18.4 ppm. The worm that sat in the stimulant water had a mean pulse rate of 15.9 ppm.
Blackworm Pulse Per Minute
Trial
Plain Water
Stimulant Water
Count #1 16 18
Count #2 14 22
Count #3 13
Count #4 20 17
Count #5
Count #6 19
Count #7 15
Count #8
Count #9
Count #10
Conclusion-
According to our results it shows that the worms in the stimulated solution have a higher average versus the worms in the plain water. This proves our Hypothesis was correct Blackworms in a stimulant solution will have a higher pulse rate than that of Blackworms in Plain water environment! However, in the future we could do more trials seeing if the worms pulse in the stimulant decline after a certain amount of time. Errors that occured are the worms would strain from the heat of the microscope but,the possibilities of future experiments are virtually endless.
Materials:
Microscope
Pipettes
Dishes with worms
Well slide
Blackworms in Plain and Stimulated Water
Timer
References:
-C. Drewes (9-04) Lumbriculus variegatus: A Biology Profile