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Measurement and observationField Trip - Marin Headlands
Submitted by: irene on 10/17/2006 Links to related content: 6-8 | 9-12 | College | Earth Science | Measurement and observation | Plate tectonics and Earth's structure | Using models and maps | Shaping Earth's surface | Field trip | Irene Salter | Plate Tectonics Box Options: read more | login or register to post comments | 2 attachments Project - Raising TroutSummary Submitted by: irene on 08/03/2006 Links to related content: 3-5 | 6-8 | Measurement and observation | Science as inquiry | Ecology | Acids, bases and solutions | Labs and projects | Irene Salter | Physiology Box Options: read more | login or register to post comments | 2 attachments Project - Raising PlantsSummary Submitted by: irene on 08/02/2006 Links to related content: 3-5 | 6-8 | 9-12 | Measurement and observation | Science as inquiry | Plant biology (photosynthesis) | Labs and projects | Irene Salter | Physiology Box Options: read more | login or register to post comments | 1 attachment 7. Frog DissectionMaterials
Submitted by: irene on 07/31/2006 Links to related content: 6-8 | 9-12 | Measurement and observation | Human Biology | Classroom activity | Irene Salter | Physiology Box Options: read more | login or register to post comments | 1 attachment 7. Flower DissectionMaterials
Submitted by: irene on 07/31/2006 Links to related content: 3-5 | 6-8 | Measurement and observation | Plant biology (photosynthesis) | Classroom activity | Irene Salter | Physiology Box Options: read more | login or register to post comments | 1 attachment 7. Flower and Frog Dissection
Summary Submitted by: irene on 07/31/2006 Links to related content: 6-8 | Measurement and observation | Plant biology (photosynthesis) | Human Biology | Classroom activity | Irene Salter | Physiology Box Options: read more | login or register to post comments | 1 attachment Field Trip - Marine Science InstituteSummary Submitted by: irene on 07/30/2006 Links to related content: 3-5 | 6-8 | 9-12 | Measurement and observation | Science as inquiry | Biology/Life Science | Ecology | Using models and maps | Field trip | Irene Salter | Physiology Box Options: read more | login or register to post comments | 1 attachment 6. Cell Energy - Bubbling YeastSummary Submitted by: irene on 07/29/2006 Links to related content: 6-8 | 9-12 | Cell biology | Measurement and observation | Science as inquiry | Organic chemistry and biochemistry | Labs and projects | Irene Salter | Physiology Box Options: read more | login or register to post comments | 1 attachment 6. Cell Energy - Colorful RespirationSummary The liquid is bromthymol blue (BTB) a non-toxic acid-base indicator that can be used to indirectly measure levels of dissolved carbon dioxide (CO2). The amount of CO2 in a solution changes the pH. An increase in CO2 makes a solution more acidic (the pH gets lower). A decrease in CO2 makes a solution more basic (the pH gets higher). The reason for this is that carbon dioxide that is dissolved in water is in equilibrium with carbonic acid (H2CO3). CO2 + H2O ↔ H2CO3 In any solution, while the majority of CO2 stays as CO2, some of it is converted to H2CO3, turning the solution slightly acidic. If CO2 is added to the water, the level of H2CO3 will rise and the solution will become more acidic. If CO2 is removed from the water, the amount of H2CO3 falls and the solution becomes more basic. Thus, acid-base indicators such as BTB can indirectly measure the amount of CO2 in a solution. For more than you ever wanted to know about carbonic acid, see the Wikipedia article on carbonic acid. For the example lesson plans developed by Bob Culler through Access Excellence at the National Health Museum. For a great time lapse video showing BTB color changes using elodea and snails, see Activity C13 from Addison-Wesley’s Science 10 curriculum. Materials
Procedure
Going Further Submitted by: irene on 07/29/2006 Links to related content: 6-8 | 9-12 | Cell biology | Measurement and observation | Science as inquiry | Acids, bases and solutions | Plant biology (photosynthesis) | Organic chemistry and biochemistry | Labs and projects | Irene Salter | Physiology Box Options: read more | login or register to post comments | 2 attachments 6. Cell Energy - Photosynthesis in a JarSummary In 1771 and 1772, Priestly conducted a series of experiments using a bell jar. It was known that a candle placed in a sealed bell jar would eventually burn out and could not be relighted while still in the jar. Priestly discovered that a plant can survive indefinitely within a jar. Thus, he tried placing a plant into the jar with the burning candle. The candle went out as before and could not be relit right away. Priestly waited several days and tried again. The candle could be relit! The plant had restored the air inside the jar! (Do not try the next series of experiments since it harms animals!) Next priestly investigated what would happen to animals. He found that a mouse placed inside a sealed jar will eventually collapse. However, a mouse can survive in a sealed jar with a plant since the plant restores the air. Priestly was the first to demonstrate that oxygen is necessary for fire and animals but that given time, plants can create oxygen, allowing fires to burn and animals to breathe. Submitted by: irene on 07/29/2006 Links to related content: 6-8 | 9-12 | Cell biology | Measurement and observation | Science as inquiry | History of science | Plant biology (photosynthesis) | Organic chemistry and biochemistry | Labs and projects | Irene Salter | Physiology Box Options: read more | login or register to post comments | 1 attachment |