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Topic: Turgor Pressure Why does a touch me not plant close? Hey!! Don't touch that plant. You will get scared. See, you did not listen to me. Don't worry!! Nothing to be scared about. Let me tell you more about this plant. This plant is called the Mimosa Pudica plant. Another name for it is "Touch Me Not" Plant. When anyone touches this plant, it closes its leaves with the help of pulvini. Pulvini are present at the base of each leaflet. They consist of cells filled with water. This water applies pressure against the walls of the cells. This pressure is called the turgor pressure. It helps the leaflets to stand upright. Now, when we touch a leaflet of the touch me not plant, specific parts of the plant release certain chemicals. These chemicals cause the cells in the pulvini to lose water. When water is lost, there is no more turgor pressure. As a result, the cells collapse, resulting in the closing of leaflets.

8:40 Never look at a plant the same way again! Come explore plant structure and the many adaptations that make plants true survivors. This clip briefly compares vascular and nonvascular plant structure before jumping into several plant adaptations.

This case study uses a jigsaw activity to introduce students to four specific plant responses to climate change: elevational range shifts, phenology shifts, community shifts, and changes in biodiversity. Students become "experts" on one of these responses by reading an article (from Nature, Science, or American Journal of Botany; not included with the case) on their assigned topic and then sharing their expertise with others in class. In order to hone their understanding and increase retention on these topics, students then learn about plant communities found in a specific system-vernal pools or seasonal wetlands typical of Mediterranean climates (a PowerPoint presentation on this topic is included). Students accomplish several small group tasks to assess how different vernal pool plant communities have responded to fluctuations in annual weather patterns and predict how these communities may respond to greater weather variability resulting from future climatic change. This case was written for mid- to upper-level ecology, plant ecology, botany, or environmental studies courses. The material covered may also be suitable for classes examining the role of weather variability/climate change in relation to plants.

Plant species belonging to divergent branches of the evolutionary tree are known to have independently evolved caffeine production. According to scientists at Western Michigan University, caffeine-producing plants have taken a number of different biochemical routes to synthesize the stimulant. Coffee, tea, cocoa, orange, and guaraná plants make caffeine using an array of enzymes and substrates, the researchers reported in PNAS this week (September 20).

This case study is centered on a real scenario from 2013 in which the Kickstarter fundraising platform included a fundraising proposal from a group wanting to use synthetic biology to make glowing plants. The proposal raised controversy because the Glowing Plant group offered to give away their genetically-modified glowing plant product to investors.  Kickstarter subsequently changed its policy to prevent use of genetically modified organisms as rewards or incentives to investors. This case study was developed for a college first-year seminar focused on the ethics of synthetic biology, and was introduced during the first week of the semester. The case uses the jigsaw teaching method to introduce students both to the mechanics of synthetic biology and to questions about how we should distribute the benefits and burdens associated with new or emerging technologies. It could be adapted for courses in introductory college biology, genetics or bioethics.

This flipped case study is formatted as a PowerPoint presentation that uses group experimentation to encourage active learning in a large science classroom. There are options for using either wet bench experimentation or an online simulation, depending on the class goals. Students learn about plant transpiration and how it affects normal plant processes (photosynthesis). The basics of transpiration are covered in an animated video viewed outside of class. The experiment and/or simulation of transpiration can be conducted in or out of class. If the class is very large, the instructor may choose to assign the experiment/simulation for outside of class (post-video) and have the students bring their data to class, or the instructor may choose to just present the students with a data set from which they can work with their groups in class. At the end, students should be able to define transpiration, explain climate effects on transpiration rates, and how transpiration rates affect the overall physiology of the plant itself, through their own hypothesis design and experimentation.

One common virus takes a sneaky route to success. It doesn't kill its leafy hosts. Instead, it makes infected plants smell more attractive to bees. That ensures this germ will have a new generation of the plants to host it in the future.

Japanese knotweed (Fallopia japonica) is an invasive plant that can be very hard to eliminate. This PowerPoint-driven case study briefly describes this plant and asks students to identify possible solutions for its control when a homeowner discovers it growing next to his house. The case was designed for an introductory college course, either a general biology course or a plant biology course, and while it can be used as a regular case, it was actually written to assess the students' ability to solve a problem and write an analysis. If you teach with cases, shouldn't you test with cases as well?

Corn was originally bred from the teosinte plant by native Mexican farmers. The morphologies of modern-day corn and teosinte plants are compared to illustrate how artificial selection can bring about dramatic changes in plants.

Such descriptions of GMOs raises fears about whether gene transfer between species is outside of how evolution operates and therefore unnatural. Research, however, has repeatedly shown the opposite to be true. In May 2015, researchers showed that practically every known species of cassava (sweet potato) contained genes from Agrobacterium, a bacterial species whose genes we have also harnessed to create other GM crops. The genes were inserted over 8,000 years ago and may have helped the tuber evolve into its current, edible form. This phenomenon of genetic transfer during evolution between species, also known as 'horizontal gene transfer' is not restricted to plants.

Healthy plants reflect more near-infrared light than stressed plants, so bright red indicates dense, growing foliage. For this reason, biologists and ecologists occasionally use infrared cameras to photograph forests. 

genotype/phenotype study using plants

Plants need sunlight to live, but they also need to block the sun's more harmful rays. Plants can't put on sunscreen or find shade, so how do they avoid getting a gnarly sunburn?

3 minute video Each father and mother pass down traits to their children, who inherit combinations of their dominant or recessive alleles. But how do we know so much about genetics today? Hortensia Jiménez Díaz explains how studying pea plants revealed why you may have blue eyes.

Explore some examples of specialized plant and animal cells with the Amoeba Sisters! This video explains how specialized cell structure suits their function.

This case study takes place at a fictional biotechnology company developing herbicides against invasive plant species. The case study focuses on five herbicides with different effects on photosynthesis. Students play the role of lab interns and explore photosynthesis and the herbicide effects by engaging in concept mapping, experimental design, data manipulation, and data analysis. The goal is to use the experimental data to predict the steps in photosynthesis that are inhibited by each herbicide. Students should come away from the case study with a process-based understanding of photosynthesis. This case study is designed for the "flipped" classroom with suggested preparatory videos and associated assessment questions included. Videos can be supplemented with textbook readings or mini-lectures. This activity was developed for a non-majors introductory biology course but it could also be used in any general biology course, including majors' courses. It might also be used to establish foundational knowledge for more advanced discussions of photosynthesis in plant biology (botany) courses.

It's one of the big mysteries of cell biology. Why do mitochondria-the oval-shaped structures that power our cells-have their own DNA, and why have they kept it when the cell itself has plenty of its own genetic material? A new study may have found an answer. Scientists think that mitochondria were once independent single-celled organisms until, more than a billion years ago, they were swallowed by larger cells. Instead of being digested, they settled down and developed a mutually beneficial relationship developed with their hosts that eventually enabled the rise of more complex life, like today's plants and animals.

Plant by plant, classroom by classroom, Green Bronx Machine is improving outcomes and changing destinies. For more on donations, click the About Us page.

In a mountain meadow in Colorado, ecologists have come across yet another example of the amazing interconnectedness of nature's flora and fauna. Black bears, by eating ants, help one of the meadow's key plant species thrive.

For at least 10,000 years, humans have been cultivating plants and selectively breeding them for fast growth, pest resistance, long-term survival in storage, and bigger and better fruit. We've been domesticating animals for just as long, selecting for traits that suited our needs, such as size, appearance, or even personality. For a few decades, we've also had genetic engineering methods for getting the characteristics we want in plants, animals, and microorganisms.