In the field of biology, it is essential to not only learn the concepts taught in classes, but also use them in a real-life application such as working in a laboratory. As a freshman biology major, I knew I wanted to gain experience with research and as a sophomore, I applied to several labs through BURA and was able to get a position in the Jensen Lab, which works with zebrafish to identify molecular mechanisms that are involved in generating and maintaining the morphology of vertebrate photoreceptors. There are two different kinds of photoreceptors in the eye. Cone cells are used to see color and detail but are not very sensitive to light. Rod cells are sensitive to light changes, depth, shape and movement. These rod cells are more abundant in the eye and consist of the outer segment, the inner segment, and the cell body which is connected to a synaptic region.
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In the case of this tragic situation, we beliieve that the labrodor should be the breed of dog that should recevie the vaccine. Labradors have very large litters (7.6 dogs per litter) which would allow the population of dogs to regenerate qucikly. Labs are also the number one dog in americam, they are also easy to train. They provide assistance to the handicapped, show competitor, and search and rescue dog, among other canine jobs.
The neuron is a highly specialized cell responsible for communicating with the rest of the body using electrical and chemical signals. Thye are compposed of many parts. The dendrites are appendages that receive information from other neurons. The soma is the cell body of the neuron that contains the nucleus, the ribosomes and other organelles. The nerve receives either excitatory or inhibitory impulses and when the signal reaches the axon hillock, an action potential is fired down the axon, which sends signals to other neurons. The nerve terminal is at the very end of the axon where the neurotransmitters are released. The nerve terminal is also part of the synapse, which contains the nerve terminal of the presynaptic neuron, the membrane of the postsynaptic neuron and the space between them, which is the synaptic cleft. The axons of neurons are insulated by myelin which is either produced by oligodendrytes in the central nervous systema or by the Schwann cells in the peripheral nervous system. Besides neurons, there are helper cells in the nervous system which are called glial cells or neuroglia. These include astorcytes which nourish the neurons and create the blood brain barrier and epidymal cells which line the ventricles and create cerebrospinal fluid. Microglia are phagocytes that work in the nevous system and the schwann cells and oligoendrytes also fall into this category.
The ability for a neuron to communicate with other cells depends on the membrane potential of the cell. The resting membrane potential which is when the cell is at equilibrium is -70mV. This is upheld by a Na/K ATPase which pumps 3 sodium out of the cell while bringing 2 potassium in. The signals that the cell recevies either makes the inside of the cell more positive, is an excitatory signal while the signals that make the inside of the cell more negative are inhibitory. Neurons are constantly receiving signals and the sum of the signals determines whether or not an action potential is fired. This is called summation. When the signal is strong enough to cause an action potential, the signal reaches the axon hillock which opens up voltage gated sodium channels allowing sodium to flood into the cell causing the cell to depolarize. When the cell reaches 35 mV, the the sodium channels close and the potassium channels open causing the cell to depolarize.
Even with a descriptive methods, there are some factors that were not controlled in the creation of the figures. For example, the time of day the photos were taken were not specified, so that could change the coloration of the tree and the moss. This could explain the reason the coloring in the replicated figure B is warmer in the replicated image. Also, even though the type of camera used was specified in the methods, it is possible the person who recreated the figure used a different type of camera or a cell phone with a higher quality camera. This could explain the clarity of the replicated figure C compared to the original figure. I was also not specific on the certain angles at which the pictures were taken so the angles that the pictures were taken at could be different. For example, in figure B, the trapezoidal shape of the pot of the tree could be because I had taken the picture at a higher angle than the person who replicated my figure. Another cause is simply human error. I forgot to include in my methods that I labeled the sporophytes and gametophytes in the original image, so the replicated image had no labels in it. Also, I had meant for all the pictures to be perfectly aligned, but by lack of detail I had glazed over the connection of figure A and C, which
While doing working in the lab during the past four semesters has taught me a lot, I believe that being able to immerse yourself in research is the best way to cultivate skills and get the experience of seeing an experiment from beginning to end. With classes, work, and other activities, it can be hard to find adequate amounts of time to perform experiments during the school year. Fellowship funding would enable me to spend the entire summer conducting this research. I would be able to concentrate on my honors thesis full time. Over the last summer, I interned as a volunteer with Leah Campbell, a post-doctoral fellow in the lab where I learned how to fin clip zebrafish, genotype them by running a Polymerase Chain Reaction and then performing a gel electrophoresis. When I first began, I had no experience with this. Throughout my time in the lab I learned a lot of techniques and by the end of the summer I was able to perform these experiments completely on my own. I am hoping to get the opportunity to build upon the skills I have acquired and use them towards my honors thesis research.
Coming in as a freshman biology major, I knew I wanted to participate in research. During the fall of my sophomore year, I applied to a few labs through BURA and was able to get a position in the Jensen Lab, which works with zebrafish to identify molecular mechanisms that are involved in generating and maintaining the morphology of vertebrate photoreceptors. There are two different kinds of photoreceptors in the eye. Cone cells are used to see color and detail but are not very sensitive to light. Rod cells are sensitive to light changes, depth, shape and movement. These rod cells are more abundant in the eye and consist of the outer segment, the inner segment, and the cell body which is connected to a synaptic region.
The specific project I was working on was collecting data for a chemical screen to see what kind of chemicals either inhibited or stimulated the growth and shedding of the outer segments of rod cells. There is some literature that concludes the light cycle plays a part of the rate of growth or shedding, but the molecular mechanism for this is unknown. The rate of growth and shedding is important because when an outer segment gets too short, the photo receptor dies and does not regenerate, leading to blindness. Discovering what chemicals stimulate or inhibit growth and shedding can lead to clinical advances in treating blindness. While measuring could get monotonous at times, it was very exciting to be contributing to new discoveries.
Now as a junior and beginning to work on my honors thesis, I am planning on following up on the research I assisted with as a sophomore. My summer plan would be to pick a few of the chemicals that were screened and pick specific doses to screen, then see if the different doses change the effect of the growth or shedding rate of the outer segments of these photoreceptors. To complete this process, I would begin by setting up fish to lay eggs, then sorting the embryos and caring for them as they mature. After 5 days, they are heat shocked which is when we would introduce the drug in different doses. After a few days of allowing them to develop with the drug in their systems, the zebrafish are fixed and embedded. They are then sectioned and the slides are then analyzed using a confocal fluorescent microscope that allows me to see where the growth began and ended. Using the Velocity software, the images would then be measured to see how much the outer segment has grown or shed. Once all the data is collected, I will analyze it statistically to conclude how the different doses either stimulate or inhibit the growth and shedding of this outer segment.
While doing research during the past four semesters has taught me a lot, I believe that being able to immerse yourself in research is the best way to cultivate skills and get the experience of seeing an experiment from start to finish. With schoolwork, jobs and extracurriculars getting in the way, it can be hard to find adequate amounts of time to perform experiments. Having the whole summer to perform this research will allow me to really see through the entire scientific process and allow me to learn by practicing these skills full time. It is also advantageous to have this lab experience when I apply for jobs in research after graduating. Over the last summer, I interned with a post-doctoral fellow in the lab where I learned how to fin clip zebrafish, genotype them by running a Polymerase Chain Reaction and then performing a gel electrophoresis. At the beginning of the summer, I had no experience with this. Throughout the summer I learned a lot of technique and by the end of the summer I was able to perform these experiments all on my own. I am hoping to get the same experience this summer where I will be able to build on all the skills I have acquired in the lab thus far and begin performing research for my honors thesis.
The jounal that I was able ot find is the American-Eurasian Network for Scientific Information This states that you must submit your manuscript in microsoft word format and then sent by email to the Advances in Environmental Biology. They also need to submit a cover letter including the authors names and affiliations, as well as a short bio.
While Drosophila Melanogaster have been used as model organisms to discover more about the genetics in humans as well as body development, only 4 Nobel Prizes have been awarded to scienticists who use this as their model organism. Interestingly, the award only is awarded to three people a year, and there is no award for math. The first nobel prize that was awarded to Thomas Hunt Morgan in 1933. He did work pertaining to being able to identify where genes were lcated on chromosomes. While Morgan received this nobel prize, two researchers in his lab who did the majority of this research. Morgan shared the prize money with them. The second nobel prize was awarded to Heramaan Muller by making a breakthrough regarding mutations and x-rays. Even though this work was done in 1930s, he was not awarded his work until 1946. The third award went to Christiane Nusslein-Volhard, Eric Wieschaus, and Ed Lewis for screening the fly genome and helping pave the way for understanding the genomics of development. Finally, the last award went to Jules Hoffman, Bruce Beutler and Robert Steinmann in 2011 for their work on innate immunity.
In eyes, there are two main types of photoreceptors, rod cells and cone cells. Rod cells allow people to see movement, depth and shapes in high or low light conditions. These photoreceptors are composed of the cell body, the inner segment and the outer segment. The outer segment is capable of both growing and shedding, however if the rod cells shed and become too short, the cell dies and does not regenerate leading to blindness. While there is some literature concluding that the light cycle plays a part in this, the molecular mechanism is unknown. In order to discover more about the molecular mechanism for the growth and shedding, we are running a chemical screen of different drugs to see how they effect the rate of both growth and shedding using zebrafish eyes as a model system. By breeding, heatshocking, embedding and observing results using a confocal fluorescent microscope, we will observe which chemicals chosen from a chemical library effect the growth and shedding of the outer segment at different doses.