Article 6 Summary Continued

Submitted by brdougherty on Fri, 12/08/2017 - 10:55

The daily activities examined in this experiment were basking, foraging running, swimming, and diving. In order to examine basking, blood samples were taken from marine iguanas that remained unmoving for at least 30 minutes. To ensure that the capturing process did not affect the lactate concentration samples were taken in under 45 seconds of capture. To test foraging iguanas they were captured between 1-5 minutes after returning to the shore and a blood samples were taken.  Running was tested on previously basking iguanas by forcing them to run from danger for 2 minutes and then a blood sample was taken. For the diving field experiment iguanas were forced to dive for 6 minutes and then allowed to swim freely. Lastly, Gleeson examined if swimming following a forced dive removed lactate from the blood of iguanas. This was tested by forcing iguanas to dive for 5-6 minutes and then allowing them to swim freely for 30-60 minutes all while testing their lactate level in their blood through a device previously implanted in the iguanas. 

Elevator Speech

Submitted by vthong on Fri, 12/08/2017 - 10:44

Our experiment tested the possible effects that caffeine had on planarian regeneration after being cut below the pharynx. We tested the planarians in two experimental groups in addition to the control group. Our control group was regular spring water, and the two experimental groups were low and high caffeine concentrations. We recorded the length of the planarians every few days and compared the relative rates of regeneration in the three groups. The planarians in the control group showed the highest rate of regeneration, followed by the ones in the low concentration condition, and the slowest rate of growth was in the high concentration condition. The measurements showed that the planarians placed to regenerate in the high concentration of caffeine actually decreased in length over the course of the experiment. With these results, the overall takeaway from this experiment was that caffeine is detrimental to planarian regeneration.

Elevator Speech

Submitted by vthong on Fri, 12/08/2017 - 10:30

Our experiment tested the possible effects that caffeine had on planarian generation. To do this, we had one control group and two experimental conditions that we placed the planarians in for 16 days. Our control group was regular spring water, and the two experimental groups consisted of a low and high caffeine concentration. The planarians were cut below the pharynx. We wanted to see the difference in the relative rates in the growth of the planarians based on environment that the were exposed to. We recorded the length of the planarians every Monday, Wednesday, and Friday until our experiment reached Day 16. The planarians that regenerated in the low concentration of caffeine showed a lower rate of growth compared to the planarians in the control group. The planarians that were placed to regenerate in the high concetration of caffeine actually decreased in length over the course of the experiment. With these results, the overall takeaway from this experiment was that higher concentrations of caffeine is detrimental to planarian regeneration.

photons

dthaley's picture
Submitted by dthaley on Fri, 12/08/2017 - 10:20

The purpose of the experiment is to observe light emitted through a diffraction grating and to measure the distance from the center point to calculate sin theta, wavelength, and frequency. One part of the experiment is to view the continuous spectrum with a diffraction grating. This will produce a virtual image of the colors of the rainbow. Measurements taken will be used to find the sin and the wavelength. 
The second part of the lab used a diffraction grating to create atomic line spectrums from lamps filled with different gases: hydrogen, mercury, and sodium. This type of spectrum is created when the molecules in the gases are exposed to energy which can produce heat, this added energy jumps the electron into a higher orbital, and when it begins to fall back to the lower level, the electron releases a photon. This photon has a distinct wavelength and frequency specific to the element that it was released from. From the emission spectra wavelengths, sin  and frequencies were calculated from the measurements collected. The formula to find sin  was a(avg)[b+a(avg)]2. The formula to find the wavelength 
dsinθ = mλ, and using the Rydberg equation 1/ λ = 0.01097(1/ nf2 - 1/ni2). Frequency was found using c= f .

Pavlovian conditioning models

dthaley's picture
Submitted by dthaley on Fri, 12/08/2017 - 10:19

The learning capabilities of planarian flatworm were evaluated by applying first-order and second-order Pavlovian conditioning models. In the lower-order Pavlovian conditioning, learning is gained by matching a conditioned stimulus (CS) with a primary driving unconditioned stimulus (US) of an electrical shock. In higher-order Pavlovian conditioning, the planarian is exposed to a sensory stimulus as preconditioning, the blue light. The CS will be paired with a shock that has a motivational value that is acquired rather than intrinsic.

RC Circuits

Submitted by kmydosh on Fri, 12/08/2017 - 09:24

Resistors and capacitors work in combination to create a circut. The process of gainging and losing charge is not instantanous. It does not happen immeadiately. A simple circuit conatins a battery, one resistor, and one capacitor. The charge leaves the postive end and flows through to the negative end. The charge cannot move through the capacitor. For example, the charge starts off at zero. Eventually it will reach a maximum. As you have less energy to move around it will eventually reach a maximum value. As the current is going to zero the charge is going to the maximum. The inital value of the current is V=Q/C. The inital value of the charge is zero. In one microsecond you will reach a percentage of the maximum charge. This is for a charging circuit. For a discharging current, the charge and current decay at the same rate. 

background poster

Submitted by dalon on Fri, 12/08/2017 - 08:17

Sweetened diets and processed foods have become common in the American diet with many different sugary substances present in multiple food sources; however, behavioral tests comparing the preferences for these different types of sweeteners are uncommon. In this experiment we analyze behavioral preferences of planarians to 3 different types of sweeteners. The three forms of sweetener observed are pure sucrose, pure brown sugar, and pure saccharin. The chemical formula for sucrose is C12H22O11 and in a similar experiment it was found that sucrose produces a rewarding effect in planarians (Ouyang @ all, 2017). The chemical formula for brown sugar is the same as sucrose however it has molasses present in it. While we hypothesis that similar results will be seen in sucrose and brown sugar it has yet to be seen if planarians have a preference between the two. Saccharin which is commonly referred to as sweet n’ low has a chemical formula of C7H5NO3S. Saccharin offers effectively no food energy but is however approximately 300-400 times sweeter than sucrose. While no experiment was done to show if planarians prefer saccharin the group is interested to see if the planarians have a preference for the artificial sweetener.

elevator speech

Submitted by dalon on Fri, 12/08/2017 - 08:11

Our poster tested sweetener preference, specifically looking at which sweetener was most favorable amongst planarians as marked by movement. According to our data, planarians most preferred cane sugar as they spent the most time directly on top of the cane sugar area, and when presented with two other sweetener options, over half of the time they continued to spend on cane sugar. We can use this data and planarians as model organisms to demonstrate that sweeteners typically attract organisms and are therefore more likely to be consumed.

Elevator Speech PP

Submitted by jmazzola on Thu, 12/07/2017 - 23:09

    We know from previous studies that salt generally has a degrading effect on most tissues, so we thought to observe the effects of different salt concentrations on the regenerative abilities of planarians. We predicted that increasing salt concentrations would lead to a slower growth/regeneration rate of the planarian head. We observed three sets of three planarians each in a control condition, a low salt condition with 1 gram of salt and high salt condition with 2 grams of salt, over three weeks. We observed the planarians a couple days each week and measured them to see how much they grew or shrunk. In the end, we found that both salt concentrations resulted in the death of the planarians, however the lower salt concentration left the bodies mostly intact, whereas the higher salt concentration left the bodies in a more disintegrated state. So, we concluded that while the salt did significantly impact their growth, further studies at lower more precise concentrations of salt are needed to fully observe the impact.

Elevator Speech ~

Submitted by jmazzola on Thu, 12/07/2017 - 23:08

We know from previous studies that salt generally has a degrading effect on most tissues, so we thought to observe the effects of different salt concentrations on the regenerative abilities of planarians. We predicted that increasing salt concentrations would lead to a slower growth/regeneration rate of the planarian head. We observed three sets of three planarians each in a control condition, a low salt condition with 1 grams of salt and high salt condition with 2 grams of salt, over three weeks. We observed the planarians a couple days each week and measured them to see how much they grew or shrunk. In the end, we found that both salt concentrations resulted in the death of the planarians, however the lower salt concentration left the bodies mostly intact, whereas the higher salt concentration left the bodies more disintegrated. So we concluded that while the salt did significantly impact their growth, further studies at lower more precise concentrations of salt are needed to fully observe the impact. 

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