I recently listened to a presentation given by the esteemed Anusha Shankar. She is a certified National Geographic Explorer and is currently moderating scientific studies at the University of Alaska. She is also working to complete her Postdoctoral Fellowship. Her presentation mainly focused on her work surrounding hummingbirds and African Grass Rats. When it came to hummingbirds, Shankar was mainly focused on how these creatures expended energy. Generally speaking, hummingbirds will die in just a mere two hours if food is not eaten. Meanwhile, humans can last a couple of days without eating. According to Shankar, the difference is due to how hummingbirds store and expend energy. Hummingbirds are constantly using energy when they fly. Unlike humans, hummingbirds have very little fat which would normally be used to store energy. These two factors lead to hummingbirds being constantly highly reliant on getting food.
Anusha Shankar’s Presentation
My favorite part of her presentation was definitely when she discussed African Grass rats. Shankar has been using these rats to study Seasonal Affective Disorder and the effects of this disease on humans. I found this part to be very ironic because she lives in an area with little to no sunlight, making her more prone to becoming depressed. Here in California, there is a lot of sunlight so residents do not have to worry as much about dealing with the side-effects of there being no sun. She said that she used lights in her room to help cope with the lack of sunlight.
One other aspect of her presentation was how we got to watch it. Our school was connected to multiple other schools through an online video chatting system. Students from other schools could ask questions and we would all get to hear their responses. I had personally never done anything like this so I really enjoyed this form of communication.
Cancer and disease have always been a part of our society. Unfortunately, in just the U.S. alone, 609,640 die every year from cancer. However, because cancers and other diseases affect so many families, doctors have been extra keen on finding a cure. Scientists and research specialists such as Mana Anvar and her team have been working to find a cure or at least develop a usable drug to treat Dravet Syndrome. Dravet Syndrome is generally caused by a mutation on the SCN1A gene and causes prolonged seizures that are extremely dangerous. Unfortunately, this disease is hard to treat so Mana has been working to find a drug that works.
One of the most interesting parts of her presentation was when she discussed her work on Zebrafish. Her team would use CRISPR-Cas 9 to try to give the fish seizures and from there work backward to try to find a usable drug. In general, I do not think a lot about how drugs for certain diseases are actually created. It was super interesting to hear about her experience as a researcher and learn a little more about the process behind creating new treatments for certain diseases.
One other topic I found interesting this season was making bacteria glow. I never realized what a complex process inserting plasmids is. There are a lot of different factors that have to line up in order for the plasmid to be accepted and for the bacteria to actually grow. I thought it was really interesting to see the bacteria colonies forming and to watch these colonies grow under the UV light. For me, I also had a lot of fun being able to “paint” with these glowing bacteria. Overall, this was probably one of my favorite seasons because of how well the topics we learned connected to modern-day life.
Have you ever worried that your dreams would not come true? I know I have. As for Diana Nyad, I know she has as well. Diana Winslow Need, now known as Diana Nyad, is an extraordinarily inspirational swimmer born in New York City, New York. At the age of 64, she successfully swam from Cuba to Florida via the Straits of Florida. This swim was around 110 miles and took her a whopping 52 hours of swimming to successfully complete. Diana Nyad is truly inspirational.
Listening to her TedTalk was very empowering. I have never dreamt of swimming 110 miles but I think I speak for the majority of the world when I say we all have goals and we all sometimes question if we will ever reach them. Diana Nyad’s talk was very inspirational because she reminded me that literally, anything is impossible. For me, it has always been easy to simply blame my lack of success on my age or the fact I do not have enough free time. If Diana had the same mindset that I have sometimes, she never would have completed her swim.
Diana Nyad’s TedTalk
This talk helped me to reflect on reaching some of my goals in my own life. While I probably will not ever swim the entirety of the Straits of Florida, there are many experiences I want to have in my lifetime. For instance, one of my goals is to complete the program A Semester at Sea. I have always wanted to do this program because it would give me to chance to see the world while learning about different cultures. As for more long term, I would love to get into whichever college I choose and hopefully find a career that fulfills me. Of course, I have many other goals in life but I am still trying to figure out where I see my future heading.
As for Diana, I am very happy she followed her dreams. She is the embodiment of what could happen if I have resilience and persevere. At the end of her Ted-Talk, she had a beautiful quote, to sum up her life and her work. She said, I’m proud of it all, but the truth is, I’m walking around tall because I am that bold, fearless person, and I will be, every day, until it’s time for these days to be done.” Well said, Diana. Well said.
If I am being honest, AP Biology was a lot more enjoyable than I thought it would be. This semester I learned so much on a wide variety of topics. The class and I studied genetics, cellular respiration, photosynthesis, and many other subject matters. My favorite part of class last semester was probably when we covered genetics. I really enjoyed genetics because the information we learned could be directly related to my life. For instance, through mapping out my pedigree I learned more about my family’s medical history. I also liked going over the topic of morality in concern to genetics. As technology continues to advance, moral questions like how much information is too much become extremely relevant. I appreciated how we set time aside in class to discuss our own views on genetic testing and the spread of genetic information in general. Many classes do not take the time to actually incorporate a student’s opinion/views so I was very thankful we got to talk about it.
While AP Biology was very fun, this class also pushed me a lot. I knew going into the year that having an AP class every day would be hard and AP Biology definitely met my expectations in that regard. While this class was difficult at times, I am thankful I decided to challenge myself for many reasons. There were many people in this class who I was not very close to before starting class this year. Through AP Biology (and our share struggle to understand the materials) I was able to cultivate many new relationships that I have a deep appreciation for. I was also able to work on my time managment skills since we have work due every day and cannot work past or before certain hours.
Some of my favorite projects that we did last semester were the Oil and Water Above and Beyond and the Cell Membrane Project. I am a very visual learner so physically completing an experiment about polarity and drawing out the cell membrane really helped me to learn the material. I also liked these because they were both group assignments. In the modern-day workplace, there are rarely times where people are not forced to collaborate with each other so I really enjoyed honing this skill.
Overall, I had a really well first semester of AP Biology. While I may not have totally crushed the final, I did do pretty well in the class at the end (and hey it leaves room for improvement). I’m glad I took this class because I like the material and the relationships I have cultivated with the people in this class. I am also thankful for all the real-world skills I am learning that I know I will need to apply at some point in my near future. I am somewhat nervous but overall very excited to see what this upcoming semester holds in AP Biology.
Meiosis is the division of sex cells. When meiosis first begins, the process starts out with one diploid cell and ends with four haploid cells. At the end, the four haploid cells have half the amount of chromosomes as the original diploid cell. Without meiosis, sexual reproduction would not be able to occur which is why meiosis as a cycle is so important.
The process overall was a bit draining. First off, doing stop motion takes a lot of time and patience and also does not result in a lot of footage. Trying to fit in the amount of audio we had into the amount of footage we had proved quite challenging. Furthermore, WeVideo was a decently new platform to work with. For us, using this tool was actually kind of hard. We are used to using Imovie so using this new tool had some caveats. Overall, the editing took a really long time but the actual product turned out pretty nicely.
Welcome to my Investigations page! Here you can find all the work I have done this year exploring deeper into biology. Enjoy!
Hey guys! I made these membrane drawings with my group in class. These pictures show the different parts of the cell membrane as well as some of the processes that occur on the membrane. Enjoy!
Lab Partners: Mckaela Glanville, Annica Kim, Viva Vorzimmer
Experiment Title: Using Chromatography to Identify the Individual Plant Pigments Involved with Photosynthesis
Purpose: The purpose of the experiment is to determine the separate pigments involved in photosynthesis as well as compare and contrast fall and summer pigments.
Background: Photosynthesis is a process that takes place in the chloroplast that converts light energy, water, and carbon dioxide into sugar. Photosynthesis works through pigments absorbing light from particle wavelength. Most plants contain both chlorophyll a and b as well as carotenes (orange) and xanthophylls (yellow). These pigments show through in the fall when the production of chlorophyll decreases. The pigments in plants can be determined through chromatography which is when chromatography paper is used to determine the different substances that make up a mixture.
Hypothesis: If samples from a green leaf and a yellow leaf on chromatography paper are placed in an acetone solution then the leaf containing more chlorophyll will have a greater Rf value then the sample with less chlorophyll.
Data:
Rf of green leaf: .938
7.4 – 1.3 / 7.8 – 1.3 = 6.1 / 6.5 = .938
Rf of yellow leaf: .781
6.8 – 1.5 / 6.9-1.5 = 5.3 / 5.4= .981
What is the basic importance of chromatography?
Chromatography allows scientists to separate and analyze different substances within a mixture. Chromatography can be used for a wide variety of important experiments such as identifying evolutionary relationships and identifying drugs in pee.
What factors allow chromatography to happen?
The factors that allow chromatography to happen are the electronegativities within the substances. The polarity of the solvent helps to decide how far the substances will diffuse up the chromatography paper.
What purpose does chromatography paper have in this experiment?
The chromatography paper allows scientists to see the different pigments as they diffuse across the paper. Given that the pigments are more attracted to the chromatography paper than the actual solvent, the pigments will stay in place on the chromatography paper.
What is the purpose of the solvent?
The solvent helps the pigments diffuse up the paper. The pigments that are more attracted to the solution move up further on the chromatography paper.
What does Rf value stand for?
The Rf value stands for the relative mobility factor. The Rf value is the ratio of the distance that the substance travels on the chromatography paper to the distance that the solvent travels.
How do you think that the Rf value is useful to scientists?
The Rf value is useful because scientists can use the Rf value of a substance to determine the identity of that substance.
What does Dunknown signify?
Dunknown signifies the distance the unknown substance traveled up the chromatography from the original marking.
What does Dsolvent signify?
Dsolvent signifies the distance the solvent traveled up the chromatography paper from the original marking.
How many pigments were you able to identify from the GREEN leaf chromatogram? Include a picture.
For the green leaf, there was one pigment.
How did a GREEN leaf chromatogram compare to a NON-GREEN leaf chromatogram? Include a picture?
The pigments on the green leaf chromatogram showed up a lot better than the pigments of the non-green chromatogram. The Rf value for the green leaf was higher (0.938) than that of the non-green leaf chromatogram (0.981). This means that the pigments of the green leaf moved farther on the chromatography paper than the pigments of the non-green leaf.
What else did you find out about pigments and photosynthesis?
Through this experiment, I found out more about photolysis. Photolysis is the breaking down of water through light. Photolysis is important because the water is split into protons and electrons. The electrons go to the chlorophyll and the protons help create the proton gradient. I also found out that chlorophyll only absorbs red and blue light and not green light like I previously thought.
What is one more question you still have?
What is the difference between chlorophyll a and b?
Hey everyone! Mckaela and I just did the oil and water experiment. We learned a lot about polarity and how molecules interact with each other… Check it out!
Chloe Powell's AP Bio Blogspot 