Past research has found that Planarians have similar addiction behaviors to humans. This led me to wonder if they had preferences for different substances. Dar and I explored if planarians had a preference for a particle sweetener. The 3 sweeteners we choose to observe were sucrose, brown sugar, and saccharin. The results show that sucrose was the most preferred sweetener followed by saccharin, and then brown sugar. The results were rather interesting because sucrose and brown sugar have the same chemical structure besides the fact that brown sugar has molasses. At the same time saccharin offers no nutritional value yet it was more preferred than the brown sugar, which made the group, hypothesis that molasses may have properties that deter planarians.
Planarians have a rare ability to regenerate their entire heads and central nervous system after being cut off. We also know that an excess of salt can have a deleterious effect on living tissues, so we wanted to observe the effects of different salt concentrations on the regenerative abilities of planarians. We cut the heads off of planarians, and then put the tails in different concentrations of salt. The control had no added salt, the low concentration had 1 gram of salt, and the high concentration had 2 grams of salt mixed into a small water bottle. There were 3 planarians for each concentration. We predicted that higher salt concentrations would lead to a slower regeneration rate of the planarian head. We measured the length of each planarian 3 days a week for two weeks.
We found that both the low and high salt concentrations resulted in the planarians dying. The lower salt concentration left the bodies mostly intact, but shriveled up, whereas the higher salt concentration left the bodies very disintegrated, often leaving the bodies in many small fragments. So, in the end, the results were mostly inconclusive, as the planarians died before we had a chance to see them grow at all. Further studies at a lower, more precise concentration of salt are needed to fully observe the impact.
This experiment did not result in a statistically significant difference in growth between the control group and the planaria living in the 31˚C water. The T-Test resulted in a P-Value of 0.999 meaning that it is highly likely that the variation observed in growth differences was due to chance. This result could be due to the time allotted for the experiment. With only 13 days, the planaria did not have a significant time to regenerate. This lead to observed growth of only about 0-0.1 cm, which was about 0.5 cm away from the planaria regenerating to their initial length. Also using a more accurate form of measuring could help the statistical analysis be more accurate we rounded to the nearest 100 mm. If we also had a larger sample size in each control it could lead to a stronger statistical analysis. Thus giving us a more accurate understanding of the effect of temperature on regeneration.
In Europe, BWA does not have a negative effect on its hosts. However, North American firs did not co-evolve with BWA which causes a hypersensitive reaction to its feeding. This results in grouting and the formation of “redwood”. Grouting describes the swelling at the branch nodes and the stunting of terminal growth; it results in loss of branch growth and an overall decline in health. Redwood refers to the reddish-brown coloration of the wood underneath the bark due to mass infestation on the main stem. This results in the decrease of water flow through the stems. After about two to three years of mass infestation in the stem, the host tree typically dies
Although there are several cases where familial ALS displays an autosomal recessive inheritance pattern, the vast majority of instances associated with either the SOD1 and C9orf72 genes show an autosomal dominant pattern. While the symptoms of the disease were first described by Jean-Martin Charcot in 1874 (Lewis Rowland, 2001), the association between ALS and SOD1 was first characterized by Daniel Rosen et al in 1993 through a combination of polymerase chain reaction (PCR) and polymorphism analysis. Prior to the study, familial ALS (FALS) had been linked to chromosome 21-4.25 but despite the presence of several candidates, the identity of the exact gene remained elusive. As SOD1 was a candidate gene, two of its five exons underwent PCR analysis followed by single-strand conformational polymorphism analysis. The subsequent audioradiograms of these tests revealed shifts in band mobility that suggested the SOD1 gene was indeed responsible for a portion of cases of familial amyotrophic sclerosis. This was later confirmed through directly sequencing the PCR amplified exons which revealed the presence of a heterozygous genotype with one normal and one abnormal allele in all of the families of interest (Rosen et al. 1993).
Based on the data from this experimental trial, it is possible to conclude that exposure to caffeine decreases a planarian’s ability to regenerate. Referencing figure 5, the slope of the line of best fit is 0.0107, indicating that the control planarians regenerated at a rate of about 0.0107cm each day. However, the planarians in the low concentration of caffeine regenerated at a slower rate of only 0.0031cm each day. The planarians in the high concentration of caffeine were unable to regenerate altogether, and instead decreased in length at an average rate of 0.0216cm per day.
In addition to causing a slower rate of generation, the increasing concentrations of caffeine represented proportionally decreasing total changes in length over 16 days. The control planarians increased in length by an average of 0.2cm in 16 days, while the planarians in a low concentration of caffeine increased in length by an average of only 0.067cm in 16 days. The planarians in a high concentration of caffeine decreased in length by an average of 0.2cm, because the caffeine caused them to shrivel and be incapable of growth.
This graph displays the difference between the planarian’s length on day 0, when the cuts were made, and day 16, when the final length measurement was taken. Each bar of the graph represents the average of this total change in length for the three planarians in that corresponding group. The average total change in length of the control group was 0.2cm, the average total change in length of the 50/50 Water Joe and Pure Life planarians was 0.067, and the average total change in length of the Water Joe Only planarians was -0.2.
This experiment was performed in Morrill 3 room 301 starting on November 15th. Three planarians were used as the control group with no caffeine, three were used as the moderate caffeine level, and three more planarians were used to test high caffeine levels. Aside from the varying amount of caffeine the same procedure was followed for all nine planarians. The experiment was done on a labeled sheet as seen in Figure 1. On Day 1, each planarian was placed in a small clear condiment cups labeled with the number of planarian 1-3 for the varying conditions. For the control group, 20 mL of Nestle water was used per condiment cup. The moderate level of caffeine was 10 mL of Nestle water and 10 mL of Water Joe. The high level of caffeine was 20 mL of Water Joe per cup. The pipet was used to transfer the planarian from the condiment cup to the large petri dish where each was measured, cut in half using a blade, and then measured again. The measuring went on for 16 days and all lengths were recorded in centimeters.
The MC1R DNA sequences were analyzed and cleaned by cropping areas that were not as reliable such as the 5’ and 3’ ends which contained poorer quality sequences than the middle sections. This part of the procedure was done following “Analysis of Canine DNA Sequencing.” Heterozygous sequences were noted for each sequence. The three files were refined and assorted into FASTA format. The overlapping sequences were assembled into one contiguous sequence using the CAP3 Sequence Assembly Program. The contiguous sequence was then compared to known sequences on the NCBI database using BLAST. Sequence matches were recorded and reviewed for potential missense SNPs. The sequence was compared to a consensus sequence on NCBI and aligned using the EMBOSS Needle Pairwise Sequence Alignment program. The SNPs were identified and recorded.
This graph displays the progressive changes in length throughout the experimental trial. Day 0 represents the day on which the original cuts were made to the planarians. After being cut, the average length of the planarians in all three groups was 0.4 cm. Days 12, 14, and 16 represent the days on which measurements of the planarian’s lengths were taken and recorded. Each of these three days displays three data points; an average length of the three control planarians (blue,) an average length of the three planarians in the 50/50 Water Joe and Pure Life environment (orange,) and an average length of the three planarians in the Water Joe Only environment (gray.) On day 12 the average length of the control planarians was 0.467cm, the average length of the 50/50 Water Joe and Pure Life planarians was 0.4cm, and the average length of the Water Joe Only planarians was 0.3cm. On day 14 the average length of the control planarians was 0.53cm, the average length of the 50/50 Water Joe and Pure Life planarians was 0.43cm, and the average length of the Water Joe Only planarians was 0.2cm. On day 16 the average length of the control planarians was 0.6cm, the average length of the 50/50 Water Joe and Pure Life planarians was 0.467cm, and the average length of the Water Joe Only planarians was 0.2cm.