2644 - CSUN ScholarWorks - California State University, Northridge

journal of Student Research Abstracts · 79
along with the consultation from my teacher, to use euglena. I coated the bottoms of two petri dishes with samples
from the euglena culture. I added "Water Joe," a caffeinated water product, to one of the dishes. "Water
Joe" contained 60 grams of caffeine to 500 ml of water. Euglena are phototropic so I used a lamp to manipulate
them to go to from one place to another. I used a piece of 2 x 2" black construction paper and I cut a small
slit about 2 mm long and 25 mm wide near the center of the paper. The paper was placed on top of the petri
dish. I hypothesized that because euglena like light and they have green pigmentation, then would form a green
colored band. After a band was obtained, I moved the paper over about 5 mm and recorded the time it took for
the euglena to move from one place to the other. Between the two dishes there was no noticeable difference in
time for the movement of the euglena. I was able to conclude that caffeine did not have any observed effects
on the euglena.
2821
ANGlE OF STEM GROWTH ON RADISH SEEDS INDUCED BY
CENTRIFUGATION.
Bruce Chien and Steve DeGusta (teacher). John F. Kennedy High School, 6715 Gloria Drive, Sacramento,
CA 95831.
Early scarlet globe radish seeds were grown on a record player spinning at 33.33 rpm to see the effect of
centrifugation on seeds. The seeds were placed at 1.38cm (represents 0.1 G), 5.9cm (0.5 G), and at 13.8 em
(1 G) from the center. The radish seeds that were placed farther from the center experienced greater centrifugal
force. The radish seeds experienced vector forces of gravity at a new vector force of angle. The problem is
to see if the stems of the radish seeds will grow according to the vector forces generated by the centrifugation.
The equation used to find the radius for the amount of G force was r =1.41 x I0- 2 g where g is the gravitation.
This tells me the amount of G force the seeds will experience at certain distance. The control was one set of
seeds on the counter not spinning with the same amount of light as the experimental. After growing the seeds
I measured the angle of the stems toward the center of the record and compared the resulting angle with the
predicted angle of growth. The results resembled what I had expected, for the seeds experiencing 1 G to bend
at 45° and 30° for 0.5 G. Most of the stems moved towards the angles that I had predicted. The differences of
data in control and experimental were not due to chance (p> 0.1). I concluded that centrifugation on radish
seeds does bent the stems at a predictable angle.
2822
EFFECTS OF CIGARETTE SMOKE ON BRINE SHRIMP.
Tiffany Lieuw and Steve DeGusta (teacher). John F. Kennedy High School, 6715 Gloria Drive, Sacramento,
CA 95831.
In this investigation I worked with the Artemia species, more commonly known as brine shrimp. I subjected
the brine shrimp to second hand smoke to see the effects of cigarette smoke on organisms. Using the top
part of a 2-liter bottle, taped to an ashtray, with a syringe covering the opening of the 2-liter bottle, I inserted
a lit cigarette on the side of the ashtray where there was an untapped opening. The syringe was used to collect
the smoke; then I slowly injected the smoke onto a concave microslide where ten experimental brine shrimp
swam. Within three minutes, some brine shrimp began to curl up, while other shrimp chased their tails in a circular
motion. Other brine shrimp reacted to the cigarette smoke by rapidly twitching and beating their trunk
limbs. Eighty-eight out of one hundred shrimp reacted to the smoke in the experimental group, while only
twenty-one of the control group reacted. The reaction to the smoke could have been due to the lack of oxygen
when the cigarette smoke was placed into the water where the brine shrimp swam. There is a highly significant
difference between the brine shrimp exposed to the second hand smoke and those that were not, which
could possibly be due to the smoke from the cigarette. (p :::;;0.001)