jkswanson's blog

SIGNIFICANCE  

    The findings of this study will be very beneficial for multiple reasons. The data we collect will give us insight into the behavior and lives of the small cellar spiders that live in basements and homes right alongside humans. Today and going forward, LED lights are the new light bulb, they are more efficient, cheaper and easier to install and use. This means that the LED light will began to have a much larger presence in the outdoors as street lamps, lights in the park, etc.. With LEDs becoming more and more prominent and mixed into our surroundings, this study will show some of the effects LED lights can have on spiders creating their webs, eating, sleeping, and just their overall behavior. Comparing the results of this study to studies about regular light bulbs effects on spiders can be very useful  in helping decide where to put LEDs up, how intense to have them, and the schedule for the LEDs. Many people also face fears of spiders, both rational and irrational. Cellar spiders are one of the most common species of spiders to reside in homes and buildings. The results of this study could be helpful for people to repel spiders from living and coming into their homes and other place. Depending on the results of this study, potentially, differences in color, brightness, and/or the duration of LEDs could be used by anyone who wants keep spiders away.

SIGNIFICANCE  

    The findings of this study will be very beneficial for multiple reasons.  The data we collect will give us insight into the behavior and lives of the small cellar spiders that live in basements and homes right alongside humans.  Not much is known about the effects of LEDS on spiders and specifically on creating a web in the presence of LEDs. Today and going forward, LED lights are the new light bulb, they are more efficient, cheaper, easier to install and use, etc.. This means that the LED light will began to have a much larger presence in the outdoors as street lamps, lights in the park, etc..  With LEDs becoming more and more prominent and mixed into our surroundings, this study will show some of the effects LED lights can have on spiders creating their webs, eating, sleeping, and just their overall behavior. This study, in part with others, can then be used to decide where to put LEDs up, how intense to have them, and the schedule for the LEDs. This study could also bring insight into the most effective ways to repel spiders from living and coming into houses and other places.

Results:

Figure 1:

TLC plates no pictures, actual plates

Table 1:

Table 2 TLC analysis for the plates:

TLC Plate 1:

TLC Plate 2:

Discussion:

In this experiment, benzoin was reduced with sodium borohydride and recrystallized to 1,2-diphenylethane-1,2-diol(0.239 g) with a recovery of 39.05 %.  The product, (1,2-diphenylethane-1,2-diol), was determined through TLC analysis and melting point. The TLC analysis showed the presence of two different compounds (seen in Figure 1).  The starting material (spot A) traveled the same distance on both the TLC plates with Rf values of .77-.79 which are very close. This is different than the recrystallized product and the crude product (spot B) in plates 1 and 2, respectively.  The recrystallized product and the crude product travel a shorter distance and therefore have a lower Rf value that are very similar to each other, .54 and .57 respectively. The co spots (spots C) show that there are two compounds presence since both contain two spots with two different Rf values.  

This means that a starting material other than the starting material has formed in both the crude and the recrystallized product.  Additionally spot B on both plates contain only one spot and neither matches the starting material spot so therefore Benzoin (starting material) must not be present in the crude and recrystallized product.  

The TLC plate is a silica gel plate that is polar, which means polar compounds interact more with the plate and don’t travel as far as relatively less polar compounds.  Benzoin was expected to travel further than 1,2-diphenylethane-1,2-diol because it is less polar. This was supported by the TLC plate and observations made. The melting point also supported that the recrystallized product (1,2-diphenylethane-1,2-diol) was relatively pure as it’s MP range was 135-137 ℃, which is two degrees, signifying purity.  The melting points for this lab is very important because it tells us how pure the substance is and in some cases is able to determine the isotope of a certain compound.

To improve purity a different substance other than HCl could be used to cause a slower reaction, which in turn would increase the purity of the product.  Yield could be increased by raising the temperature slightly when mixing in this lab as it takes a long time for the solids to dissolve which could mean some is being left out or not completely dissolved.  The warming would allow for all the starting material and materials involved to be used to their fullest.

Post Lab question:

This would mean that there would be 3 different compounds in the mixture.  

The spot with the same Rf as the starting material is the starting material, and the other two spots with different Rf values are most likely the expected product, the secondary alcohol.  The difference between the last two non starting material spots could be because they are different isomers of the same compound.

Sodium Borohydride Reduction of Benzoin

Purpose:

The main goal of this experiment if to use sodium borohydride to reduce benzoin to 1,2-diphenylethane- 1,2- diol.

Reaction Scheme:

Experimental Procedure:

Benzoin(0.5g, 2.36 mmol) and ethanol (4 mL)were added to a 25 mL erlenmeyer flask. The mixture was swirled at room temperature until the benzoin was completely dissolved.  Then sodium borohydride(0.1 g, 2.64 mmol) was added in several portions over 5 minutes. It was swirled at room temperature for 20 minutes. The mixture was cooled in an ice bath for 15 mins. Then water(5 mL) and HCl(0.3 mL, 6M) were added to the mixture. After 15 minutes,  water(5 mL) was added to the mixture. The mixture was then vacuum filtered to collect the product, using small amounts of ice cold water to wash the flask. The filter was left running with the product to dry for 15 minutes. The crude product was weighed, and the melting point was determined.  Around 1 mg was put aside for TLC later. The rest of the product was recrystallized using minimal acetone, it was washed with hexane during the vacuum filtration process. The crystals were dried overnight. The mass and the melting point of the 1,2 -diphenylethane-1,2-diol were determined during morning hours.  

For the TLC analysis, benzoin(1 mg), crude product(1 mg) and recrystallized product(1 mg) were all dissolved in separate vials with a 9:1 solvent of ethyl acetate.  The TLC plates were then marked and spotted accordingly:

The solvent travelled until around 1 cm from the top of the plate.  The TLC plates were dried and spots were observed and marked under the UV light.  The TLC papers were then set in the iodine chamber to stain the spots. The Rf values were then calculated and recorded.

The fossil needed to support the phylogeny is a common ancestor of both the hippo and the whale and would consist of characteristics from both species.  Specifically it would have the pulley shaped astragalus. The common ancestor of the whale and hippo diverged and created 2 seperate species, hippo and whale. This was done when the whale mutated and lost the oulley shaped astragulus, while the hippo still has that characteristic to this day.  The common ancestor is an animal that consists of both whale and hippo characreristics, which characteristics other than the pulley shaped astragulus, we may never know. The requirement for the pulley shape because using the idea of maximum parsimony leads us to want the least amount of evolutionary changes. It would make much more sense and be much easier for the whale to lose the pulley shaped astragulus and the common ancestor of the whale and the hippo to have it, than for the common ancestor to lose the characteristic and for the hippo to independetly gain it back. It makes much more sense to say the common ancestor contained the pulley shaped astragalus, and had some whale characteristics.

Question 1: The fossil needed to support the phylogeny is a common ancestor of both the hippo and the whale and would have characteristics of both.  Specifically it would have the pulley shaped astragalus. The common ancestor of the whale and hippo diverged and created 2 seperate species, hippo and whale, and did this by the hippo keeping its pulley shaped astragalus and the whale losing the pulley shape.  The common ancestor is some sort of combination that contains the pulley shaped astragalus but also some characteristics of the whale. The requirement for the pulley shape is because it would be near impossible for the common ancestor to evolve from a pulley shaped astragalus ancestor and then lose that trait only to gain it back in the hippo but not in the whale.  It makes much more sense to say the common ancestor contained the pulley shaped astragalus.

Question 2: The definition of homology is a characteristics that is shared or very similar among different species shared by their one common ancestor.  The definition of homoplasy which is, shared characteristics between species that wasn’t present in the common ancestor, is shown in the phylogeny when both the monotremes and the Therians both develop the unattached bone even though their common ancestor had the bone attached to the jaw.  This is a basic example of homoplasy and is likely due to living in similar conditions and having somewhat similar behaviors that benefited having an unattached bone. The phylogeny shows homology with the evolution of the 3 inner ear bones. Up until the Morganucodon the species all have the same inner ear and have it attached and to the lower jaw bone.  This shows homology because the ancestor is passing on its genes and the species has the same inner ear as their ancestor. One specific example is how the red bone keeps getting smaller, it happens to all the common ancestors as the time goes on and when the therians and monotremes both have very small red bones and a very similar shaped green bone which are both derived from their common ancestor meaning those traits are homology traits.

If all the dogs in the world were to inevitable die, but I am able to save one breed I would have to save the black labrador retriever.  These dogs are in my opinion the best dogs ever. They are so unbelievably cute when they are younger and grow up into beautiful and handsome animals.  They are also a great family dog and are very happy and energetic. This is exactly what i need in a dog, the energy for fun but also the good nature for the family.  The black lab have a really close connection to their owners as well and love to socialize with the entire family and the neighbors as well. The labs are also very easy going and extremely friendly, just what everyone needs, a good friend in their life.  From a logical standpoint black labs would be agreta dog because they are capable of providing help in so many different situations. The name itself comes from the dogs being used to retrieve small game while hunting. They are also very good for service animals because of their friendliness, easy going, and general love for their owner.  Some labradors even go as far to become police K9s and do things like sniff out drugs or bombs. As someone who loves dogs and has changed my favorite dog breed more than ten times I would undoubtedly pick to save the black lab. At the end of the day a dog is a man's best friend and a black labrador retriever is the perfect dog to be best friends with.  

• Why does a multipolar neuron have lots of dendrites but only one axon?

• Multipolar neurons are the most common shape for neurons in your brain--what advantages do multipolar neurons have over unipolar or bipolar neurons?  Are there any disadvantages?

• How many synaptic connections does a single neuron usually make?  Take a guess, or do some outside research to answer this one!

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    The primary function of a neuron is to both transmit information and to process it.  The multipolar neuron is shaped so that it has many dendrites and only one axon. This allows for an efficient processing and integration of information from multiple presynaptic neurons.  These neurons have only one axon because it takes a lot of energy to send information to postsynaptic neurons. Many dendrites allow for multiple presynaptic axons to deliver information to one post synaptic neuron.  The unipolar neurons only have one process, a single axon from the cell body. They are only good seen as sensory neurons. Bipolar neurons have an axon and a dendrite and are also sensory neurons. Multipolar neurons are superior as they can collect more information and be used for both motor or association neurons, allowing for muscle movement or communication among the CNS.  There are no really big advantages and disadvantages as they both perform unique tasks that are needed. Each average neuron is connected to about 10,000 synaptic connections.

Synthesis of Cyclohexane via Dehydration of Cyclohexanol

Purpose:

The purpose of this lab is to synthesize cyclohexene via an acid-catalyzed dehydration of cyclohexanol with phosphoric acid, in addition to purification of product through fractional distillation and analysis using chemical tests and gas chromatography.

Reaction Scheme:

Experimental Procedure:

The hotplate was turned on upon arrival to around 400℃. Two g of cyclohexanol and .8 mL of 85% phosphoric Acid were placed into a round bottom(rb) flask along with boiling chips.  A fraction distillation apparatus with aluminum foil wrapped around the cylinder containing copper mesh. The mixture was then heated over the aluminum block to fractionally distill at a rate of one drop per second with drops collected in a collection vial.  Once there is a about a 10% of the mixture left in the rb flask, distillation was stopped. After the distillation stopped the contents of the collection vial were moved to a test tube. In the test tube two layer were observed and both layers were mixed using the pipette, then using water to wash. Using the pipette, the lower aqueous layer was removed and placed in waste. Then 1mL of 1M sodium hydroxide was added to the tube and again through washing the liquids were thoroughly mixed and the bottom layer was removed to waste. Then 2 mL of brine were added and the contents of the tube were mixed well via washing and the bottom layer was removed to waste.  

Using a clean pipette, the organic layer was transferred from the test tube to a new clean

collection vial.  Several spheres of CaCl₂ were added in the new collection vial and the contents were gently swirled until the spheres were no longer clumped together, then the vial was left capped and to dry for 5 minutes. The product was then transferred to a preweighed vial using the pipette, leaving the CaCl₂ spheres. Chemical test where then performed on the cyclohexene, then 3 drops of potassium permanganate was added to each tube. After swirling, the cyclohexane remained purple in color, while the cyclohexene formed a pinkish color that turned colorless.  A few drops of the product were left in the vial for the gas chromatography test and IR spectroscopy.

Question 1: The fossil needed to support the phylogeny is a common ancestor of both the hippo and the whale and would have characteristics of both.  Specifically it would have the pulley shaped astragalus. The common ancestor of the whale and hippo diverged and created 2 seperate species, hippo and whale, and did this by the hippo keeping its pulley shaped astragalus and the whale losing the pulley shape.  The common ancestor is some sort of combination that contains the pulley shaped astragalus but also some characteristics of the whale. The requirement for the pulley shape is because it would be near impossible for the common ancestor to evolve from a pulley shaped astragalus ancestor and then lose that trait only to gain it back in the hippo but not in the whale.  It makes much more sense to say the common ancestor contained the pulley shaped astragalus.

Question 2: The definition of homology is a characteristics that is shared or very similar among different species shared by their one common ancestor.  The definition of homoplasy which is, shared characteristics between species that wasn’t present in the common ancestor, is shown in the phylogeny when both the monotremes and the Therians both develop the unattached bone even though their common ancestor had the bone attached to the jaw.  This is a basic example of homoplasy and is likely due to living in similar conditions and having somewhat similar behaviors that benefited having an unattached bone. The phylogeny shows homology with the evolution of the 3 inner ear bones. Up until the Morganucodon the species all have the same inner ear and have it attached and to the lower jaw bone.  This shows homology because the ancestor is passing on its genes and the species has the same inner ear as their ancestor. One specific example is how the red bone keeps getting smaller, it happens to all the common ancestors as the time goes on and when the therians and monotremes both have very small red bones and a very similar shaped green bone which are both derived from their common ancestor meaning those traits are homology traits.