For this unit we had to complete various projects. These projects consisted of a hardware cladogram project, a species evolution timeline and a lab about alu repeats. For the cladogram project, all students were split up into groups of 4. Our task was to use hardware pieces and organize them to show an imaginary evolutionary process of the hardware pieces. After they were organized we had to create a story for the evolution. We had to use forms of speciation and describe the evolution to show and explain the evolutionary process. We then arranged an actual cladogram showing where we decided to put the different pieces and why we put them where we did. With the species evolution timeline we worked in pairs. Our task was to pick an organism and create a five stage graphic representation about the evolution of that organism. For my project my partner and I chose to do our project on the tiger. For the graphic representation we chose to do a slideshow. Both of these projects were worked on in class for about 3 weeks. For the alu repeat lab We were given a procedure that we followed to use gel electrophoresis on our own DNA to see if we contain specific alu repeats. This was a longer more complicated project so we got a week to work on just the lab itself.
The picture shows my groups final result for the cladogram project and the slideshow is the final product of the timeline project. The two projects shared similar content being that they were both about evolution and speciation. Many concepts were introduced during these projects, including various forms of speciation, natural selection, and evolution. For the cladogram stories we used the process of speciation (geographic isolation etc) to describe. The tiger project more showed evolution. I learned about common ancestors and the relation they have to the modern tiger and the adaptations of all the different stages of tiger. Evolution- Change in the heritable characteristics of biological populations over successive generations. Natural Selection- The process of the environment allowing certain traits to become more dominant and killing off the disadvantageous traits. Natural selection works through four elements: variation among traits, competition for resources, survival, reproduction of the organisms that survived passing on the advantageous traits Survival Of The Fittest- The organism best suited to its environment will survive. Speciation- The process of creating a new species. Adaptation- A trait which increases the likelihood of survival for the individual who exhibits that trait.
The alu repeat lab was all about introducing labs and lab proceduresso we can gain skills and learn about what to do for future. For this particular lab we followed a procedure to get cells from our cheek, isolate the DNA from the cells, perform PCR to replicate the DNA, and then use a process called electrophoresis to sequence it. It was valuable to know the steps so that we could be successful in running the experiment. We spent a while learning about the procedure, PCR, and DNA sequences. DNA- DNA (Deoxyribonucleic acid) is a molecule that carries the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms. Alu Repeat- "Alu repeats are approximately 300 base pairs in length. They got their name from the fact that most carry within them the base sequence AGCT which is the recognition site for the Alu I restriction endonuclease, a type of enzyme that cuts DNA at a specific site. There are over 500,000 Alu repeats scattered throughout the human genome. On average, one can be found every 4,000 base pairs along a human DNA molecule." BABEC ALU PCR 2017 Lab PCR- Polymerase chain reaction is a technique to amplify a single copy or a few copies of a segment of DNA, creating millions of copies of a particular DNA sequence. Gel Electrophoresis- A technique used in laboratories in order to separate macromolecules based on size. IT applies a negative charge so proteins move towards a positive charge. For DNA, smaller sequences move faster because they contain less proteins. DNA Ladder- a set of standards that are used to identify the approximate size of a molecule run on a gel.
Reflection Over the span of the three projects I learned many different things. One of which was how to perform a PCR lab. PCR is needed for gel electrophoresis because it takes very few strands of DNA and replicates them into millions of identical copies. Techniques like these are a crucial part of biology and played a big role in the Alu repeat lab. Another thing that I learned was how new species are created. Speciation can be caused by various reasons. For all three projects, there were aspects that I needed to improve upon. The biggest issue was time management. My group finished the clatogram project with very minimal time left. Improving on time management is a big plus because it help you finish your wok on time and not in class the day it has to be done. Another issue I had was trying to be precise as possible while measuring liquids. My DNA did not show up on the gel, this playing a major role in that. Being able to measure precisely is a very important skill that I will acquire over time.