Friday, April 7, 2017

Unit 8 Reflection

Unit 8 was about evolution and how and why species evolve. Evolution can be measured as a change in the frequency of an allele in the gene pool. The gene pool is the the total number of genes in a population. One of the main forces that sparks change in the gene pool is natural selection,  the theory that the "winners," or individuals with better traits survive and reproduce to pass their genes on while the individuals with traits that don't help survival die and take their genes with them. We explored this in the Hunger Games Lab. When we tested this, the individuals with traits that helped them pick up food increased in population while the individuals with bad traits nearly died off. The allele frequency was graphed and showed the allele frequency change, showing that evolution was occurring.
The type of natural selection exhibited in this lab was directional selection, where one extreme phenotype, in this case the pincher, was favored so the phenotypes shift towards that. Stabilizing selection is where the average phenotype in the middle are favored and extremes are not. This keeps the population from changing. Disruptive selection is when both extremes are favored and the graph splits in two. This is often the beginning of speciation.
http://www.course-notes.org/biology/topic_notes/33_behavioral_ecology/fecundity_selection


Natural selection is not the only thing that can change allele frequency. Genetic drift is when random acts kill random members of the population, eliminating them from the gene pool. This can be harmful because it lowers genetic variation. Gene flow is movement of alleles between populations, and mutations can also change allele frequency. Sexual selection traits are traits that increase chance of mating but do not help an individual survive.

New species are created in a process called speciation. When a species is reproductively isolated, they begin to drift apart until they are two different species. They become different species in a process called evolution. There is evidence to prove evolution exists. There are certain traits that modern day organisms have that are useless but would have been useful to ancestors. Also, similarities between species point to a common ancestor in the distant past.

Earths vast history is split up into eras, periods, and epochs. Mass extinctions mark the end of many of these. Each time period has different characteristics.

This unit was not a very difficult unit, but the scale of the Earth's timeline is hard to comprehend. Some questions I have are how did unicellular organisms turn into multicellular organisms and then plants and animals. Also how did asexually reproducing organisms evolve and become sexually reproducing.

I have had a chance to be more assertive in the geological timeline project. I have realized that there is a time to be a leader and be slightly more aggressive for the better of the group, but also a time to sit back more passively to better the group. But mostly, I have been assertive by leading with clear logical steps and listening to the ideas of others.

Wednesday, March 29, 2017

Hunger Games Final Analysis

1. In this lab we simulated generations of a population by having each generation have to get enough food to survive and reproduce.
2. The pincher was the most successful at getting food because it could do it very easily and quickly, leading to survival and reproduction.
3. The population did evolve because the allele frequency changed. The allele frequency was roughly equal in the beginning but by the third generation the A allele only consisted of 3% of the total alleles and the a allele was 97%. This is a drastic change in the allele frequency, and it showed in the phenotypes as most of the populations were pinchers, with few knucklers and no stumpys while the amount of each phenotype was equal in the beginning.
4. The food placement was often random and reproduction usually created a random offspring (given that the traits were present). Sometimes the food was not random and favored some over others. This could affect evolution because it can favor some without the best traits and cause some with the best traits to die to to chance.
5. If the food was smaller it may favor pinchers even more, but if it was large it may favor stumpys instead. If the food source changes or one food source goes down or extinct individuals with certain traits who were not favored before may be favored then.
6. the results may have been different if there was no incomplete dominance. There would be no knucklers, only stumpys and pinchers. At one point in the lab the stumpys went extinct but came back thanks to the knuckers. If they went extinct with no incomplete dominance they wouldn't be able to come back.
7. Evolution is caused by natural selection. Natural selection picks the individuals with the best survival traits to survive and reproduce. By weeding out the bad traits, those soon disappear or become less common while the better traits become more common, changing the population.
8. Individuals often mated with other individuals of the same phenotype, which cause the knucklers and stumpys to stick around. This relates to sexual selection found in nature. To increase chances of survival individuals sometimes cheated to get their food and stole from others. This can also happen in nature.
9. In evolution populations evolve. Natural selection acts on the genotype which affects the phenotype. Natural selection affects what genes are passed from parents to offspring which determines their traits.
10. What are more examples of events or things that could change a population? How have humans affected this process?

Saturday, March 18, 2017

20 Time Garden Project Update

Lots has happened in the past few weeks pertaining to my 20 time garden project. My path has been redirected slightly, but in a good way. I talked with Mr. Fitzgerald, a science teacher at Redwood Middle School, about the Redwood school garden. He is in charge and has a lot of ideas on how to make the garden and the campus a better place. I would like to dedicate my 20 time to helping him achieve this. He has ideas on planting native plants around the school to beautify the campus and teach students about the importance of native plants. He also has projects planned for the garden such as a greenhouse and a worm composting bin. I have spent time researching these things to ensure these projects are as successful as they can be. I would like to further research these topics and make a landscape plan for the native plants.

Monday, March 6, 2017

Unit 7 Reflection

This unit was about ecology and some of the harmful effects humans have on the planet. One of the most important concepts in ecology is trophic levels and the food web. This explains how energy moves through an ecosystem and also shows how an ecosystem can collapse. Population is another factor that influences ecosystems. Populations change frequently and are dependent on factors like water, resources, food and space. When the growth of a population levels out, it is said that the species has reached its carrying capacity. Humans have not reached the carrying capacity yet but population growth has slowed down. Limitations of resources are the main limitation for species. To keep resources available, several crucial cycles such as the water cycle, carbon cycle, phosphorous cycle, and nitrogen cycle.



Humans are exploiting these resources and endangering ecosystems and species across the planet. Habitat destruction, climate change, and over exploitation are some of the main reasons the planet is this way. We need to act fast to preserve biodiversity, slow climate change, and reduce the amount of resources we use and pollutants and waste we create. If everyone makes a conscious effort to save the Earth, it will add up for the benefit.

Some questions I have are is it too late? What will happen when we exhaust all the natural resources? How are animals adapting to these changes? What can we do to help?

Our conservation biologist project went pretty well. We worked well as a group to complete the project on time. Everyone finished their share of work so we didn't have to worry. Like all group projects, it could be frustrating at times because you have to compromise and things don't always go as planned.

On the self assessment, I was not surprised with my results. I am fairly assertive but also sometimes passive. In my everyday life I have noticed that I do not always speak up when I probably should. I think if I act assertive like it says in the video, it will definitely make me a more assertive person.

https://www.thinglink.com/scene/732996661223096321

Monday, February 13, 2017

Saratoga High School Garden

In short, 20 time is spending 20% of your time on something you are passionate, in the form of a project or anything else you can think of. It is meant to be creative and self motivated. The essential question I am asking is could there be a garden at Saratoga High. For my project, I am researching, and if possible, I want to see what needs to be done to create a rooftop garden, or any garden, at Saratoga  High. I have always liked gardening, and I know that there are many benefits to having a garden at a school. SHS does not have a garden, so implementing a garden could help many people. My goals are to have either a garden at the school, or have the administration or staff strongly considering a garden by the end of the year. I will measure my progress by researching and answering all of my obstacles and questions that need to be answered to get this built. In the future, I hope to use class time to  figure out logistics involving the garden, and contacting administration in hopes they will support this project.

Tuesday, January 31, 2017

Unit 6 Reflection

This unit was about biotechnology, its uses, and the ethical questions it raises.  We learned how DNA can be recombined and inserted into a new organism through a plasmid. By inserting a gene into a plasmid and inserting the plasmid into bacteria, the bacteria will treat the new gene as its own and produce whatever protein it codes for. After introducing the plasmid to bacteria, they place the bacteria in food to make them grow and then put them into the antibiotic the plasmid provides resistance too. This ensures that all bacteria without the plasmid will die.

To learn how to analyze DNA and how to measure the lengths of the strands of DNA we did the gel electrophoresis lab. http://nakulbiology.blogspot.com/2017/01/candy-electrophoresis-lab.html We cut out DNA using restriction enzymes and tested their lengths by running them through a gel.

The pGLO lab incorporated all the things we had learned about biotech. We had several different samples of bacteria and treated each with different things. After the lab, as expected, the bacteria with the pGLO gene inserted, the ampicillin resistance, and the arabinose glowed under UV light.  http://nakulbiology.blogspot.com/2017/01/pglo-lab.html


I understood this unit pretty well. It was not very long and the hands on labs helped me in my understanding. While reading the concepts of the labs I was confused, but after doing the lab it made perfect sense to me why everything happened as it did. Seeing the concepts in action really helped me see what was going on. I wonder how biotech will play a role in society in the future. Will altering multi-cellular organisms be common? Will we ever alter human DNA or clone a human?

I think I have done a good job on my New Years resolutions. I finished my chapter notes early so I wasn't stressed or piled up with work. Also, I finished most of my homework assignments early or on time. I could still improve by preparing for tests sooner instead of procrastinating my studying.

Saturday, January 28, 2017

pGLO Lab

1.
Plate
Number of Colonies
Color of colonies under room light
Color of colonies under UV  light
-pGLO LB
covered
brownish yellow
whitish blue
-pGLO LB/amp
0
N/A
N/A
+pGLO LB/amp
100~
brownish yellow
whitish blue
+pGLO LB/amp/ara
22
brownish yellow
glowing green
2. The bacteria from the +pGLO LB/amp/ara plate gained two new traits. The transformed bacteria are resistance to ampicillin and the ability to glow under UV light. They did not die in the presence of ampicillin, and glowed under the light.

3. Each transformed bacteria must have multiplied into a colony, so about 100 bacteria were transformed in the +pGLO LB/amp. The bacteria that did not pick up the plasmid would have been killed by the ampicillin. Probably half of the bacteria died in the plate, so probably over 250 bacteria were present in the 100 micro-liters.

4. The purpose of arabinose is to "turn on" the GFP or Green Fluorescent Protein. This causes the bacteria to glow green under UV light. 

5. There are several uses for GFP for biologists. It can be used as a marker when inserting a gene into a cell. If the cell glows, it means the other gene inserted is also being expressed. The protein has also been altered to react to different wavelengths and express several different colors. 

6. Another practical application of genetic engineering is in food production weather it be animals or crops. Genetic engineering can make an animal or plant stronger, bigger, or more resistant to disease. 





Source: https://embryo.asu.edu/pages/green-fluorescent-protein