Saddleback Journal of Biology - Saddleback College

Spring 2010 Biology 3A Abstracts
13. MOTILE RESPONSE OF MADAGASCAR HISSING COCKROACH GROMPHADORHINA
PORTENTOSA TO PRESENCE OF NECROMONES. Darren McAffee and Carly Purcell. Department of
Biological Sciences, Saddleback College, Mission Viejo, CA 92692, USA
Many animals have been observed displaying necrophobic behavior toward their conspecifics,
especially within a population. This study was conducted to observe the short term and long term motile
responses of the Madagascar hissing cockroach (Gromphadorhina portentosa) to recent conspecific
corpses. We hypothesized that G. portentosa would avoid a dead member of its species by increasing its
distance from the corpse in both short term and long term trials. To test the hypothesis, we constructed a
board and numbered an 11 by 11 grid, we then used 120 live and two G. portentosa corpses. We then
recorded distances between the corpse and the live animal. The data collected implies that G. portentosa
has no significant necrophobic behavior. (p = 0.41 and 0.20 for the two experiments). Necrophobic
behavior has been demonstrated in other studies. However, the results of this study reject that hypothesis.
This experiment has implications on understanding the degree of necrophobic behavior in cockroaches
and phylogenetically similar animals.
14. METAL RETETION OF TIN AND IRON IN AN AQUATIC FRESHWATER PLANT (Elodea
canadensis). Tyler Finck and Matt Tolles. Department of Biological Sciences, Saddleback College,
Mission Viejo, CA 92692, USA
Metal cations can have an adverse effect on many types of plants in the environment. They come from
many different sources and diffuse into the soil and the water where plants retain these metals and can
start to perish. The experiment investigated the metal retention of iron and tin in the freshwater plant
Elodea canadensis and tested for a significant difference between the retention of iron and tin. In the
experiment, samples of Elodea canadensis were put into solutions of known concentration of tin (II)
chloride, iron (III) chloride and DI water as the control. Samples were left in the solutions for five days
and then samples were taken out of the solutions and allowed to dry off and weighed. Then, samples were
crushed with known volumes of DI water and then strained. The resulting solutions were tested for
absorbance. Using a Beer’s Law Plot obtained from known concentrations of tin (II) chloride and iron
(III) chloride, the concentrations of retained metals were obtained and used to calculate the percent of iron
and tin retained by mass. The mean percent of iron by mass retained using 0.01 M FeCl 3 solution was
0.34 ± 0.7% (± se) and the mean percent of tin retained by mass using 0.01 M SnCl 2 solution was 1.17 ±
0.9 % (± se). These results show a significant difference (p = 0.02, two tailed t-test) between the retention
of tin and iron in Elodea canadensis. These results are consistent with the hypothesis that plants retain the
different metals in different amounts.
15. THE EFFECT OF ELEVATION ON THE METABOLIC RATE OF MICE, Mus musculus. Hannah
Giclas and Khodayar Khatiblou. Department of Biological Sciences, Saddleback College, Mission Viejo,
CA, 92692, USA
The effect of temperature on the metabolic rate of mice (Mus musculus) has been previously
tested; however, we were wondering whether variance in elevation had an effect on the metabolic rate of
these mice. The experiment may provide a better concept of altitude acclimation in these small rodents.
We predicted that the metabolic rate would be greater at high altitude. We measured the metabolic rate of
Mus musculus at sea level and at high altitude (2,064 meters) using a manometer and respirometer setup
to calculate the mass specific metabolic rate of each mouse, using the time taken to use 10 cc of oxygen.
The mean mass specific metabolic rate of the mice measured at sea level is 4.09 + 0.247 mL O 2 /g/hr (+
se, n=10). The mean mass specific metabolic rate of the mice measured at high altitude (2,064 meters) is
12.34 + 0.743 mL O 2 /g/hr (+ se, n=10). A one-tailed paired t-test showed that elevation has a significant
effect on the metabolic rate of mice (p=0).
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Saddleback Journal of Biology
Spring 2010