Drafts

    In this lab, the feeding habits of tetrahymena thermophila were observed. Tetrahymena are unicellular predatory ciliates that live in fresh water everywhere. They feed on bacteria and reproduce both sexually and asexually. In order to examine the feeding rates of the tetrahymena, five samples of glutaraldehyde were prepared. Glutaraldehyde is a solution that kills the tetrahymena without harming their tissues. Five samples were prepared in order to collect samples of the feeding tetrahymena at time zero, ten, twenty, thirty, and forty minutes. After the tetrahymena were submerged into the India ink, samples of the tetrahymena feeding on the ink were put into the glutaraldehyde at those given time periods. After the experiment was finished, the feeding tetrahymena were observed under the microscope at four times magnification. Within each sample, ten different cells were observed and the number of dyed food vacuoles within each cell was recorded. The dyed food vacuoles within the cell show that the India ink was consumed by the cell due to the process of endocytosis that was performed in order to obtain food. As the forty minutes progressed, we noticed that there were more dyed food vacuoles within each cell than in the earlier observed time periods.

Students were tasked with finding a spider web somewhere on the University of Massachusetts campus and photograph it. In addition to this, students were tasked with creating a figure using these photographs, which included a map for reference. A detailed methods section describing where the spiderweb was photographed and the specific approach used to photographing and editing figures needed to be written. These methods were to be followed by another student, with the attempt to recreate the original figure. Once a replicant was created, students had to observe differences between the figures.

The goal of these tasks was to simulate a research report, giveing students practice at writing them, as well as creating figures for the report. Following another students methods demonstrated the need to be highly specific and precise when describing what is done. Overall, this project was designed to help students understand how to more accurately present and describe their methods in a well written research report.

When taking photographs of the spiderweb, there were a number of factors to control for in order to obtain similar pictures. Things such as the time of day, amount of light, and weather needed to be accounted for. In addition to this, the object used for accurately representing scale had to be noted, as well as where it was held in relation to the spider web. Furthermore, distance from the spiderweb, and the angle at which the photograph was taken had to be taken into account.

Similar factors had to be controlled when describing the editing done to create the figure. The size the photographs were scaled to was noted, as well as their general arrangment. How labeling was implimented on the figure was to be controlled. This included the color, font sizes, and location of the labeling.

To find the spiderweb, I left class on Friday afternoon around 4pm and took a left out of the doorway, walked to the end of the hall, and took another left towards the stairs. Friday was a sunny day with a high temperature around 60 degrees Fahrenheit.  I walked down one flight of stairs when I came to the back entrance of the Morrill Science Center. I took a left out of the doors and walked in the parking lot between shade tree lab and Morrill until I passed Morrill 2 and was in the small parking lot across from Morrill 4 South.  On the opposite side of Morrill 4 South, there were 4 parking spots with a brown rock wall on one side. About 75% up the wall above the curb that lines the right side of the parking lot there was a spider web between two stones. The spiderweb was between the 9th and 10th stones, counted up from the curb.  The spider web was attached to three smaller rocks and one bigger rock. There was a piece of tan material stuck within the spider web, making it stick out.

To take the first vertical picture, I got much closer to the web. Only the 4 rocks surrounding it and the full length of the web were shown in my photo I angled my phone’s camera directly at the web, from the left side.  I made sure my phone was focused on the web and not on the rocks, so the left barrier rock was blurry in my image. Directly in the middle of the top quarter of the picture was the small tan filament. Where the middle rock in the photo turned was slightly right to the direct middle of the frame.  The angle my camera was at makes the rocks look like they are pointing at about a 15 degree slant above the horizontal. The lower right hand side of the web has a light brown coating over part of the web.

I then began to make the  map. Using scribblemaps.com I located the parking lot in which I found the spider web. I then began to label “Morrill IV South” at 42.390238005 degrees North and -72.524533868 degrees West.  I did this by clicking the “abc” button in the top left corner and then putting the label in around the place I wanted it. Then, I clicked on the label and entered desired latitude and longitude.  I followed the same process to label “Wilder” at 42.390352903 degrees North and -72.523756027 degrees West. I then labeled “Morrill II” at 42.389915101 degrees North and -72.524363548 degrees West.  And finally I labeled “The University Club” at 42.389897272 degrees North and -72.523683608 degrees West. The resulting shape was a horizontal rectangle.

I then labeled the place in which I found the spider web. I searched for the University Club and a map of the area came up.  I placed the gray cross directly in front of the red car in the set of 3 cars on the map. I then selected the small circle tool in the top left toolbar on the website.  The area of the circle I put on the map was 85.71 meters squared with a radius of .01 km and a circumference of .03 km. At first, the circle showed up with a red outline and filled in green.  I selected the eraser tool and clicked on the middle of the circle to erase the green and leave a red outline. To obtain the map I kept the cross directly in the middle of the circle and zoomed in all the way to that point. From there, I clicked the negative zoom button twice.

I then started the screenshot of the map by clicking Control+Command+4.  I started my mouse in the top left corner just under the settings box and between North pleasant street and the sidewalk.  I then dragged the mouse to the right over to Stockbridge Road. I then dragged the mouse down past the lower labeling of Stockbridge Road on the map.  That saved the image to my desktop.

To take the third picture, I put my black sweatshirt down on top of the ledge and focused the camera so that the University Club was in the top right corner of the frame.  The picture was vertical. The 5 windows on the northern facing side of the building were visible in the shot, but only one second floor window and one first floor window were visible on the Western facing side.The fence was also visible in the frame.  While there was some space between the right end of the fence and the edge of the picture, the left side of the fence was not visible in the picture. There were 15 black fence posts visible in the frame with my black sweatshirt folded partially blocking the view of the bottom of two leftmost posts.  Since I took the picture at a slight angle, the right hand side of the frame goes up to about the middle second floor window. The left hand side of the frame only goes up to what would be the equivalent of the top of the first floor of the University Club if a line had been drawn from the left top corner of the picture over to the house, running parallel to the brick wall. The bottom left hand corner of the picture was almost touching the bottom of the brick wall on that side.

I took the vertical pictures on an iPhone 6.  I created the map with scribblemaps.com. I made the .png file with the pictures in Powerpoint.

Using Powerpoint, I dragged the three pictures onto one slide and organized them in the following order left to right: zoomed in web photo, map, and surroundings of web.  I then deleted the existing text boxes. The pictures were aligned so that their size could be maximized while still being next to each other with a small margin. I made the two vertical photos the same size and centered them to the horizontal photo and I centered all of them to the middle of the slide.  I then added small text boxes to the lower left hand corner of each photo. I made the zoomed in photo: A, the map: B, and the surroundings photo: C. I then highlighted each of the letters and clicked on the black A with the red line under it, making the letters red. I then clicked the insert tab and then shapes button to select the “right arrow” to point from the left side to the web.  The size of the arrows in my photo was comparable to the size of one of the stones. I then selected the “down arrow” to point to the location of the spider web from above. I made the “down arrow” about the same size as the “right arrow”.

As the temperature is increased in a reaction, the reaction will proceed faster. This is due to the increased collisions of molecules within the solution that is undergoing the reaction. When the temperature is increased, the kinetic energy of the molecules is increased and causes more collisions to occur. This allows the reaction to occur faster. The activation energy is decreased when the temperature is increased. The activation energy is the minimum amount of energy to start a reaction. This is because the increased amount of collisions between molecules allows bonds to break easier and the reaction to proceed at a faster rate, requiring less energy for the reaction to start. According to the graph that was created with the data collected in experiment four (the natural log the the rate constant k, over the inverse of temperature in kelvin), the activation energy can be found through the slope of the graph. In this case, the slope is negative. This demonstrates that as the temperature is increased, it takes less energy required to start the reaction. The Arrhenius plot is an accurate way to solve for variables in the Arrhenius equation. Some possible variables one could solve for is the activation energy (slope equals the  negative value of the activation energy divided by the gas rate constant) and the natural log of A (the y-intercept of the graph). The rate constant is increased as the temperature is increased. The rate constant is solved by dividing the rate of the reaction by the multiplication of both the concentrations of each solution used. Due to the fact that the rate had increased as the temperature was increased, the rate constant value increased as well. This is because the the rate was in the numerator of the rate constant equation. As the numerator got larger, so did the rate constant.     

Evolution is driven by natural selective processes but has no end goal or “perfect” structure or creation. The evolutionary development of species is driven by the opening of a niche and the fulfillment of that area to the best degree. Over time, this can result in structures that are similar in design or function between species. However, as taxonomists or biologists, it is important to understand the underlaying commonalities of the common ancestor of the similar species. The structure in question could either by the result of a shared common ancestor and the further development of the trait to fill a niche. These structures are known as homologous structures. An example of such structures would be the bones in the arm of a human and wing of a bat. On the surface they are different structures, but the bone shape and structure appear in similar shape and structure due to sharing a common ancestor. However, similar traits can arise because of convergent evolution, a process where evolutionary pressures cause for the need of the structure. The resulting structures from this kind of evolution are known as analogous structures. An example of this would be the wing of a bird and the wings of an insect. While they both developed wings, the structures themselves are derived from different evolutionary pressures. There is not a shared common ancestry between the two enclaves that would have given rise to wings in both.

Classical conditioning occurs when stimuli that control reflexive behavior are paired together. Pavlov, the scientist that discovered this concept, came across this finding during his unrelated experiment with salivary glands. Although he was not a psychologist, this was a major finding that affected many aspects of physiology and psychology. His experiment consisted of quantifying saliva from a dog under conditions of food being in front of them or no food being in front of them. As he understood that the salivary glands involuntarily produce more saliva when a dog sees food in front of them, it came to his surprise when the salivary glands of the dogs started working without food in front of them. He came to realize that the dogs were anticipating food, so since they understood from repetition that sitting in the lab with Pavlov meant eating food, their salivary glands would produce saliva before the food was even brought out. This confused Pavlov at first; after more research he came to the conclusion that the neutral and conditioned stimuli paired together, thus creating the term ‘classical conditioning’. These stimuli can be innate and automatic, meaning that they happen spontaneously and do not need to be learned. This explains why human bodies can anticipate a reaction; for example, humans scrunch up when next to a person blowing up a balloon. They don’t know that the balloon will pop, but from past experience their body has learned to automatically react in a tense way. These concepts all fall under classical conditioning. 

One of the most important concepts of eyesight is depth perception. Depth perception is what allows humans to distinguish 3-D objects from one another, and is what has helped humans evolve through time. In order to understand depth perception and how it develops in humans at a young age, experiments have been created to test this skill. Some tactics used are called ‘visual cliffs’, which are apparatuses that look like cliffs but are actually just small drop-offs. These cliffs cause no harm to the participant. If the participant is able to tell that there is a drop off, then they will avoid the edge of the cliff. However, if participants are unable to see the depth in the drop off, then they will walk on the glass where they would drop off. This experiment is used at different age groups to tell when depth perceptions comes into play throughout development. This experiment was also used to test depth perception of animals, including goats, chicks, dogs, rats, and lambs. The results of this experiment do not explain whether depth perception is a learned or innate skill; only some children walked across the cliff, and others were hesitant or did not at all. However, through other experiments it is evident that children must learn to understand depth perception through their experiences. 

Nomally fish have an opening on thir snout called a naris. A naris is essentially the fish's nose and is packed with olfactory receptors. Water enters the naris, and leaves through a posterior naris. Some fish have this posterior naris in their mouth, where it is refered to as a choanae. The water will then enter the gills and exit the fish body that way. The lungifsh has a special case of Naris however, where both the posterior and rostral ends are within the mouth. It has been highly debated whether or not this may be refered to as a choanae.

African lungfish live in very wet areas which are prone to completely drying up. During this dry period, the lungfish will burrow into the ground and make a chamber for itself. It will then fill this chamber with large amounts of mucus, forming a coccoon like structure. The lungfish can live in thi cacoon fo months at a time, until another wet period begins. During these wet periods is when the lungfish nest and lay their eggs. The female will create a burrow and lay its eggs in a chamber, which will be filled with decaying plant material. The male lungfish guard the egg chamber. Due to the need for african lungfish to breath actual air, and not soley oxygen from water, while guarding these eggs the males will develop pelvic gills. Pelvic gills work in the opposite ways of respiritory gills. These gills will expell oxygen from the males body and oxygenate the surrounding water. In thi way the embryo's within the eggs will be able to breath more easily. The male lungfish will only have to surface for a gulp of air about once per hour.

A map was included in the figure to show where the web was located.  To avoid copyright issues, the map was taken as a screenshot from OpenStreetMap.org. To find the location, I typed in the closest permanent fixture near the bush which was Franklin Dining Hall. OpenStreetMap.org is not too detailed so I screenshotted a larger area to show more buildings, and the whole Permaculture Garden. This screenshot was wider than it was tall. The screenshot showed from the Shade Tree Lab past Clark Hall and the grass area past Franklin. Due to the large area covered in the map, I included a red circle which showed the exact location of the web on the bush. In order to not confuse the viewer, I also constructed a key in the bottom right-hand corner that showed the same circle and wrote location of web next to it. The key was placed onto a white background that was outlined in black to make it easily seen.

The figures that were created have similarities, but there are also many differences. Between figure 1 and figure 2 a common difference is with the labels. In the second figure the font is larger, darker, and a different type of font. When looking at the individual panels between the figures differences also arise. For example, in panel A the picture is taken at a different angle. Due to the different angle of the photograph figure 1’s includes a lot more of the plant’s pot. In panel B there are differences in the lighting. The difference causes a shadow over the plant.