Wednesday, October 21, 2015

Angiosperms: How the Disappearance of Bees Put Flowers At Risk

By Zack Griggy, San Marin HS

          Plants are unique organisms. They have unique cell structures, ways of making energy, and reproduction. There are many different kinds of plants, but a category of plants called angiosperms makes up 80% of plants. But some of these angiosperms are at risk, as bees and other pollinators, which are vital to angiosperm reproduction, are disappearing.
         Plant reproduction varies among different kinds of plants in two significant ways. The two distinguishing factors that divide the kingdom Plantae are seeding and flowering. Angiosperms are the only group of plants that makes both flowers and seeds.
The various parts of a flower.
         Flowers are the reproductive system of an angiosperm. In a flower, two structures in particular play a vital role in plant reproduction. These parts are the pistil and stamen of a flower. The pistil consists of the ovary, the style and the stigma. The ovary is a small are in the bulb of the flower where eggs are stored. Atop the ovary is the style, a narrow region of the pistil that elevates the stigma. The stigma is the tip of the pistil that catches pollen and directs it down a tube so it can fertilize an ovule. The stamen consists of anthers and filaments. The anther rests atop a filament, which is a long narrow structure that supports the anther, and produces pollen, which can fertilize ovules in the ovary. The plant uses pollination to move pollen from the stamen to the pistil. However, the anther is not capable of pollinating on its own, as the pistil and anther are separated by a small distance. Something needs to pollenate the flower, whether it be wind or a pollinating insect, for the plant to be able to reproduce.
          Bees are unbelievably important pollinators. According to the Michigan State University, bees play a huge role in the environment by maintaining many plant communities. Many of these pant communities are farmed for food. Most fruits and nuts, along with cotton and alfalfa are maintained by bee populations. We need bees for our food and as our population grows, so will our need for bees. 
          Unfortunately, the bee population has been declining over the past 50 years. The decline of the bee population is due to many causes, including pesticides, colony collapse disorder (in which worker bees leave their queen and a few young and nursing bees), predators, and carnivorous plants. These causes are serious threats to the bee population and therefore a serious threat to us.
          Angiosperms are flowering plants that make up 80% of the plant population. They are at risk because bees, their primary source for pollination are disappearing. This can lead to agricultural problems for humans when bees cannot pollinate all of our crops.


To learn more about the disappearance of bees, attend Dr. Amber Sciligo's research presentation on Wednesday, October 21st at Terra Linda High School, 320 Nova Albion Way, in Room 207 from 7:30 to 8:30. 

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

Sunday, October 18, 2015

Pollinators, Predator-Prey Relations, and Pursuing Your STEM Interests: an Interview with Biologist and MSS Speaker Amber Sciligo

by Talya Klinger, MSS Intern

Dr. Amber Sciligo, a scientist in the department of Environmental Science, Policy, and Management at UC Berkeley, researches the interactions between insects, plants, the environment, and human economies. Whether she directs her focus to examining self-fertilizing carnivorous plants, observing how native bee communities enhance crop pollination, or finding the optimal level of crop diversity for sustainable farming, Dr. Sciligo’s research has important implications for the wild world of botany. Attend her research presentation at Terra Linda High School, Room 207, from 7:30-8:30 pm on October 21st.
In Dr. Sciligo's words:
1.      How did you originally get interested in ecology and evolution?

Multiple life events led me down this path. The first was in my high school biology class, when I was taught how to catch insects and curate them as if they were to be kept in a museum (arrange their body parts and pin them so that they would dry out and be preserved). I LOVED it. I thought I would become an entomology museum curator. By the time I entered college though, I had changed my interests and thought I would save the dolphins (this was back in the 90s) and signed up for the marine biology major at UCSC. Then I took a scuba class in my sophomore year and damaged my ears. I realized my place was probably not underwater, so I changed my major to Ecology and Evolution, a new major that had the same prerequisites as marine biology. That’s when I took another entomology class, curated insects again, and was reminded how much I loved them! So from then on, I took classes that allowed me to specialize in the ecology and evolution of plant-insect interactions. And the rest is history.

2. Why did you decide to research sundew plants?

I kind of fell into the study system. Normally, one picks a study system to ask a research question. In this case I had my question in mind (is there pollinator-prey conflict in carnivorous plants in New Zealand and how do they deal with it?) without more than a vague idea of where I would conduct the work. I knew I wanted to study carnivorous plants and to ask this question. I knew that I wanted to go to graduate school in New Zealand. And when I put the two together, I landed on the system of Drosera (sundews), because it was the only feasible carnivorous plant that New Zealand had to offer. At the time, I didn’t realize that Australia, just a hop, skip and a jump away, had close to 200 species of carnivorous plants of many types, while NZ only had 12 species of two types. But I had chosen NZ, so sundews are what I got!

3. How do carnivorous plants satisfy their needs for insect pollinators and insects as food at the same time?

They do a pretty incredible job attracting different kinds of insects to their traps and to their flowers, usually by visual cues such as colors, or by emitting different smells from the traps and flowers. Often, smaller insects like ants and tiny flies will get trapped as prey, which provides the plants with the nutrients they need. Larger flies and bees will visit the flowers to provide pollination. Sometimes pollinators get trapped as prey. Maybe they were visiting the flowers and the trap was too close and the pollinators fall in or get tangled up. This can be bad for the plant if they need that pollinator to bring pollen from another flower in order to make seeds. But if the plant doesn’t need this, if it can self-fertilize without many inbreeding consequences, then catching a big juicy pollinator would provide a great feed for the plant.

4. What impact will your research on crop diversification and bee communities have on agriculture?

My current work is looking not just at how crop diversity improves native bee communities, (which is an important finding on its own as it demonstrates a way to leave land in production and support biodiversity at the same time), but also how crop diversity and other practices such as crop rotation, cover cropping, mixing annual and perennial crops, and planting flower strips or hedgerows affect multiple ecosystem services at once, e.g. pollination, natural pest control, and soil and air quality. This allows us to see whether farming techniques that improve biodiversity on a farm provides benefits or tradeoffs to ecosystem services (e.g. plants that attract pollinators might also attract pests, but then they might also attract natural predators of those pests). Farmers don’t think about each of these things independently, they see their farms as a whole system with pests and pollinators, and birds and everything else all interacting at once. So it’s important that if we are going to conduct research that results in management recommendations, then we need to study the farm as a whole too. Otherwise we might make conservation recommendations that are unfeasible and won’t be adopted.

5. Whats your advice for high school students who are passionate about ecology and environmental science?

Find what aspects about these fields specifically interest you and dive in! If you have a more broad interest then seek out as many opportunities as you can to expose yourself to multiple aspects of these fields (there are many) and run with those that bring you the most curiosity and excitement. Volunteer to teach younger children or other community members. Teaching is the best way to learn about something. And look for opportunities to work in research labs at universities. There you can learn what parts of the scientific process you like the most. And maybe you’ll find a system that really fascinates you and you can end up studying that for a senior thesis project at a university, or on your own if you prefer.

I would add that while the scientific research world needs enthusiastic students like you, there are many important roles for people who love the natural world: scientific research is one way to go, teaching in schools or public forums is another, or sharing your values through writing, painting, song or other artistic avenues is also a great way to inspire others around you to pay attention.

6. One last question: do you have a favorite carnivorous plant?

Well, to be honest, I’m not really familiar with too many species. In NZ, there are only 12 species and most of them are really, really small and easy to miss. For instance, my study species ranged from only 1/2”-4” in height. I always wanted to find Drosera pygmaea, whose sticky-trap rosette is only 0.25” in diameter!! It’s no wonder I never found them though…they are so small.

I am also fascinated by the bladderworts (Utricularia spp.). They too are very small and were also at my study sites. You can only spot them when they send out a tiny flowering stalk from the body of water in which they reside. The traps are underwater and act like a vacuum to catch tiny swimming insects. I don’t know how they manage to lure the insects into their little bladders, which is why I find them so interesting. They also have very pretty flowers of bright colors, which is not characteristic of the sundews.

To find out more, come to the upcoming MSS presentation at Terra Linda High School, on Wednesday, October 21st, 7:30 to 8:30 p.m. at Terra Linda High School, 320 Nova Albion Way in Room 207. 
Dr. Amber Sciligo's Marin Science Seminar profile

Tuesday, October 6, 2015

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.

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 

"Transportation Research Panel" - An Interview with En-Ya Zhang from the MSEL Transportation Team

by Shoshana Harlem, Terra Linda High School En-Ya Zhang is a Sophomore at Terra Linda High School. She is part of MSEL's Transportati...

About Us

Marin Science Seminar is a one-hour science lecture/presentation with a question and answer period open to all interested local teenagers, educators and community. Seminar sessions are held 12 Wednesday evenings during the school year, from 7:30 to 8:30 pm in room 207 at Terra Linda High School, 320 Nova Albion Way, San Rafael. Seminar speakers are scientists, mathematicians, engineers, physicians, technologists and computer programmers. The topics presented are in a specific area of the speaker’s expertise, geared to interested high school students.