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Carnivorous Plants

by Jane Casto, Terra Linda High School Freshman

Carnivorous plants is a term often associated with flies and Venus fly traps. There is much more however, to learn about these organisms, and about their complex functions that allow optimal survival and ideal food supply. Scientists have been unraveling the true genius of these plants for years, and even now, breakthroughs are being made in research. To begin, we answer the question: what is a carnivorous plant? 
Carnivorous plants, or insectivorous plants, are plants that have adapted to consuming and digesting insects and other animals. These plants work in a variety of ways based on their species, of which there are 600 known to man. The basic understanding of the makeup of carnivorous plants is uniform throughout the different species. Carnivorous plants have adapted to a low-nutrient environment, making digestion of invertebrates optimal, as it is a low-nutrient energy method of consumption.
the Venus fly trap’s deadly leaves, the vibrant trap ready for action

In the example of a Venus fly trap, this ability to digest small insects and organisms is remarkably dependent on the transfer of electrical signaling. According to ScienceLine, “Each trap is actually a modified leaf: a hinged midriB . . which joins two lobes and secretes a sweet sap to attract insects.” This modified leaf is constant throughout all carnivorous plants, while the sap it produces varies in color, sweetness, and other qualities. Following the example of a Venus fly trap, the sap can attract virtually any small creature, and thus, the Venus fly trap often digests small frogs along with the usual fly. When the actual trap of the Venus fly trap is open, the red belly is exposed for all invertebrates to see. Once the prey has been attracted to the trap, the lips of the trap, or the lobes, close within one tenth of a second! So how does a plant move so quickly?
The answer is within the lobes of the Venus fly trap, where three or more small hairs lie. These hairs act as sensors, and if something brushes against two of these hairs, or brushes against one hair twice, the lobes of the plant will snap shut within 30 seconds of initial contact.
small hairs on specialized leaf, or lobe, of the Venus fly trap.
The science behind the closing of the trap is in the pressure caused by something brushing against the hair. This mechanical energy is translated into electrical energy, causing a small electrical signal. This electrical signal is enough to open pores within the center of the lobe, which allow water flow between the cells on the surface of the lobe. Thus water is transferred from the inner layers of the cells to the outer layer of the cells. During the transfer of water, the pressure within the lobes is drastically changed, causing the lobes to invert. This is how the effect of the Venus fly trap is achieved. 
These beautiful and deadly plants have a unique way of maintaining survival, and in turn are incredibly interesting to learn about and study. 
More on carnivorous plants and when
insects fall victim to them
during the October 21st seminar,
7:30 – 8:30 P.M.
Terra Linda High School, Room 207
320 Albion Way, San Rafael, CA 94903
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E-Cigarettes: A Subtle Danger?


By Zack Griggy, San Marin HS

          E-cigarettes, or electronic cigarettes, are marketed as a healthier and safer cigarette. But is it really? Multiple organizations, such as the Centers for Disease Control and Prevention and the World Health Organization have found that they are not at all safer that traditional cigarettes.

Newer e-cigarettes sometimes don’t resemble
traditional cigarettes at all.

          A traditional cigarette burns the leaves from the tobacco plant. Tobacco is a plant that naturally contains nicotine, the main addictive agent in cigarettes. Nicotine is also used as a strong insecticide and is so strong that a drop of pure nicotine can kill a person. When tobacco is burned, nicotine is released in the smoke. The smoker can then inhale the smoke and experience a high feeling, which is caused by excess levels of dopamine from the nicotine. In addition to

tobacco,cigarettes can also contain thousands of toxic chemicals, the purpose of which could be anything from making cigarettes combustible to enhancing the addictive effects of the nicotine.

          An e-cigarette, on the other hand, vaporizes liquid nicotine, and releases vapor. The process of smoking e-cigarettes was dubbed “vaping” because of this process. The e-cigarette is composed of a cartridge that contains e-liquid, an atomizer that heats the e-liquid, a battery, a sensor that determines when someone is taking a drag and activates the atomizer, and, sometimes, a light that simulates smoking. When a person decides to take a puff of the vapor, the sensor detects this and activates the light and atomizer. The atomizer, once activated, vaporizes the e-liquid and then releases the vapor so it can be inhaled.

E-cigarettes are composed of five parts. The orange section is
composed of the sensor and cartridge. The metallic silver section is the
atomizer. The white section is the battery and light.

          E-cigarettes are widely marketed as a safer way to get high off of nicotine, but the FDA has found that contrary to the marketing, e-cigarettes are not safe. E-cigarettes are not yet regulated by the FDA. This means that e-cigarette manufacturers do not have to list any or all of the nefarious substances found in the e-liquid. So, when someone “vapes,” they inhale all sorts of unknown chemicals. With
e-cigarettes, one might be inhaling a few toxic chemicals or a few thousand. However, e-cigarettes are slightly healthier than traditional cigarettes, mainly because e-cigarettes do not result in as much smoke as traditional cigarettes.
          To make matters worse, e-cigarette use is on the rise. E-cigarettes were invented in 2003, but has only recently gained popularity. Now, it is the most commonly used tobacco product in US high schools, and from 2013 to 2014, e-cigarette use among high school students tripled from 660,000 students to over 2 million students. E-cigarette use is clearly a growing problem. Marketing, mostly the TV marketing, was attributed to this recent spike in e-cigarette usage.
          E-cigarettes in spite of their marketing, are not safe products. E-cigarettes contain nicotine, a poisonous chemical, and all sorts of other unknown toxins. Because of marketing, e-cigarette use is increasing. E-cigarettes are slightly healthier than traditional cigarette because there is not nearly as much smoke produced.
       
Sources
1.http://healthliteracy.worlded.org/docs/tobacco/Unit4/1whats_in.html
2.http://www.drugabuse.gov/publications/research-reports/tobacco/what-are-medical-consequences-tobacco-use
3.http://www.nbcnews.com/tech/tech-news/vaping-101-how-do-e-cigarettes-work-n88786
4.http://www.nbcnews.com/health/health-news/5-facts-about-e-cigarettes-fda-no-its-not-ban-n88746
5.http://www.cdc.gov/media/releases/2015/p0416-e-cigarette-use.html

To learn more about e-cigarettes and the risks attributed to them and other important health issues, be sure to join us Wednesday, October 7th, to hear Julie Pettijohn MPH of the California Department of Public Health discuss these important topics at Terra Linda High School, 320 Nova Albion Way, in Room 207 


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Chemosynthesis in the Deep Sea

Chemosynthesis In the Deep Sea
by Jane Casto, MSS Intern, Terra Linda High School
     
          The deep sea- where cold, stable pressures and darkness rule. Within that darkness lies life; a broad spectrum of biodiversity. The most fascinating thing about the deep sea, however, lays within what goes against lifeforms on land. 
          On land, plants and animals alike require some form of energy. The same is true in the deep sea, but one thing, particularly about plants, is quite different. Photosynthesis, the process plants use to turn sunlight into usable energy through chlorophyll, is almost always the method that plants use to get said energy. However, in the deep sea, quite a difference can be seen with that process.
          One of the reasons as to why deep sea ecosystems, such as hydrothermal vents, do not use the process of photosynthesis is obvious. Little sunlight reaches that far down into the ocean. With that in mind, however, the question presents itself: how do these ecosystems get their energy?
          Jenna Judge has studied just that. Her research has been following Marine Biology, specifically the deep sea and, our answer, chemosynthesis. Chemosynthesis is the process in which energy is obtained by reactions of inorganic chemicals, occurring within bacteria and other living organisms. 
          “Chemosynthesis also seems to be fueling ecosystems at organic substrates, such as whale falls and wood falls.” Jenna said during her presentation, Patterns of Specialization in the Deep Sea, “We found that rather than sunlight fueling this reaction, it’s reduced molecules such as sulfide, and in other cases, methane, than can fuel these microbial metabolisms.” 
          According to wiseGEEK.org, the process relies on oxidation, or redox reactions. Organisms, namely bacteria and those that belong to the kingdom archea, use chemosynthesis to manufacture food. This food is used as a carbohydrate, made of carbon dioxide and water, rendering it usable for the bacteria just as a carbohydrate would be usable to us. 
          While the deep sea is one of the most extreme examples of chemosynthesis, believe it or not, chemosynthesis is also found on land. The key is that chemosynthesis occurs where sunlight is not present. Therefore it can occur in a variety of places above land, i.e. in soil, in the intestines of mammals, and in petroleum deposits. In fact, some scientists believe that due to the tendency of chemosynthesis to take place in extreme environments, it may feature prominently on other planets depending on weather patterns. 
          The deep sea has many unexplored aspects. It is nice to know that some things are no longer a mystery, and it is also exciting to think about the fact that it is not yet fully explored, leaving room for ventures for years to come.
Wednesday, September 9th, 2015
7:30 – 8:30 pm
Terra Linda High School, San Rafael
Room 207
        
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Interview with Dr. Katie Ferris of UC Berkeley

by Angel Zhou, Branson School

Monkey Flower 

Monkey flowers and mice – two radically different things. Yet, biologists, like Dr. Katie Ferris, are studying how native monkey flowers and mice have adapted to drastically different environments. 
Dr. Ferris currently works with Dr. Michael Nachman at UC Berkeley, using genetic sequencing and samples of monkey flowers and mice to show how organisms are often adapted to their local environment and that these adaptations are genetically based. 
To learn more about Dr. Ferris and her work with Monkey flowers and mice, read the following interview:
1) How did you decide to enter your field of work?
I decided to become a biologist pretty early on in life. When I was little I loved being outside and interacting with the natural world, especially with plants. Because of my attraction to plants I often got in trouble for picking flowers in my mother’s garden. When I was three years old I picked off every single bright green new hosta lily shoot that popped out of the earth. My mother was furious that I had laid waste to her hostas. After she calmed down a little she told me that when I grew up I should be a botanist because then I could pick any plant that I wanted without getting in trouble. The notion stuck and I pursued biology throughout high school and into college. In college I got a job in a lab that studied plant evolutionary genetics and learned a lot of new and exciting things through doing my own research. That experience is how I became interested in my current field of the genetics of adaptation in wild organisms.
2) Describe your typical day at work as a geneticist. What are the best parts of your job? What are the worst parts?
My typical day at work involves several different kinds of activities, which is something I like. Typically I will attend a scientific talk on something related to my interests, do hands-on work with mice (or monkey flowers in my former job), spend an hour or two doing molecular biology in a wet lab and of course spend a little time working on my computer analyzing data or reading scientific papers. The work with animals and in the wet lab usually involved working with undergraduate students who volunteer in the lab in order to participate in research. Some of the best parts of my job are getting to work with students and trying to spread my love of biology and scientific research. I also enjoy the precious and satisfaction of laboratory work and the personalities of the mice. The worst part of my job is when I have to spend a lot of time dissecting dead mice. I did not go into medicine for a reason 🙂
3) How did you decide to study monkey flowers and wild mice specifically? What conclusions have you drawn thus far in your research?
I decided to study monkey flowers when I was interviewing for graduate school. I visited a lot of different labs that studied plants, but the monkey flowers were by far the most captivating. They are bright yellow, happy little things and closely related species live in an incredible range of different environments from old copper mine tailings to salty coastal sand dunes. They are just really cool plants. I became interested in wild mice because of the work my post-doc advisor had done on the genetics of mouse coloration. He found the genetic changes that caused light colored desert mice to become dark when they lived on black rock outcrops. The mice that live on the dark rocks can then blend in to their surroundings and are less likely to be eaten by predators. I like making hypotheses more than drawing conclusions, but I would say that the main conclusion I have drawn from my research so far is that organisms are often adapted to their local environment and that these adaptations are genetically based. I have also concluded that biology is very complicated 
4) What is your ultimate goal in studying the genetics of adaption and speciation?
My ultimate goal in studying the genetics of adaptation and speciation is to understand better how the world around us works. I want to understand which genes are involved in important traits and if the same genes are used repeatedly to evolve the same traits in different organisms. In short, I want to know if the genetic basis of adaptation is predictable in any way. I also just generally want to contribute new knowledge to the scientific community. A better understanding of the genetic basis of ecologically important traits like drought tolerance or coat color can also be used by scientists in applied field to help improve agriculture or medicine. 

Dr. Katie Ferris, UC Berkley
To learn more about the genes and species’ adaptation to extreme environments, join us on Wednesday, April 1st for Dr. Katie Ferris’ seminar, “From Monkey Flowers to Wild Mice: A Tale of Genes, Adaptation and Extreme Environments” in Room 207 at Terra Linda High School in San Rafael. For more information, visit Marin Science Seminar’s Facebook page: https://www.facebook.com/events/850586588342167/
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