Today we held a class discussion focusing on the variables tested in the Baggie Garden experiments. To begin, students considered how their own manipulated variable affected seed germination. We then collected data from each group and used that information to identify temperature as one of the key factors in determining whether a seed will germinate. We also made the observation that seeds in the presence of water at room temperature did germinate, while seeds purchased from the store and kept dry at room temperature do not germinate. Therefore, water is another key factor for seed germination. Finally, we revisited the process of cellular respiration, identifying oxygen as the final requirement for seed germination.
Following the discussion, students had two options for the remainder of the class period. First, they could choose to read about cellular respiration in the textbook (pages 358-359, taking notes on the three stages of cellular respiration). Alternatively, students had the opportunity to build molecules using our new molecular modeling kits. Instructions for both activities can be found in the attached slide deck. Two students successfully modeled glucose, shown both in linear form (below left) and in ring form (below right).
Today marked the final day of observations and data collection for the Baggie Garden experiment. Before looking at their bags, students received instruction about the process of data analysis (see attached slides). We discussed the importance of providing written context to data table content, as well as things to consider when selecting the appropriate type of graph for a lab report. After entering their final observations of their baggie gardens in their lab notebooks, students had the option of taking their bags of seeds home and continuing to make observations outside of class for extra credit. We will be in the computer lab on Thursday, and students are encouraged to write the Materials and Procedure sections of their lab reports using Microsoft Word in advance of Thursday.
Note: Highline Public Schools students receive a free copy of Microsoft Office 365 for use at home! Students should use their school email and password to log in at https://login.microsoftonline.com/ to download the software.
As we continue through our unit on energy, matter, and organization, we will deploy our new molecular modeling kits. The kits, provided courtesy of our Donors Choose grant, will enable students to gain experience modeling molecules in three dimensions. In a previous lesson, students modeled cellular respiration using two-dimensional paper molecules of glucose and oxygen (which they converted to carbon dioxide and water using scissors and tape). We will be using our molecular modeling kits to model the process of photosynthesis, with various learning opportunities available to help explain the baggie garden results. Time permitting, we will also use the kits to model how glucose models can link together to form more complicated molecules like starch and cellulose. Students will have opportunities to model amino acids and nucleic acids as in future units.
Want to learn more about the exciting field of chemistry? Visit Theodore Gray’s Periodic Table website (look familiar?) to learn about all of the known elements. Then check out “Hunting the Elements” and skip ahead to 31:58 where the host introduces the concept of proton number as the definition of what makes elements unique. For the next 15 minutes or so, the host meets up with Theodore Gray – for extra credit, write up a summary of what you learn from this segment!
We wrapped up the week with a final day of observations of the baggie gardens. Students once again measured radicle growth, sketched seed germination and labeled parts, and measured the temperatures of the locations where their seeds were stored. Students were also encouraged to relocate their bags away from the cold windows to a warmer part of the room. We will observe the seeds again on Monday and then make a decision about whether to extend or conclude the experiment.
Observations were in full-swing today. We began class with a brief review of how to create a data table. Students were also introduced to seed germination vocabulary and instructed to sketch out and label the parts of visible to them as their seeds germinate. The slides are attached here. Several students took advantage of the temperature probes and recorded the temperature of their seeds in each of the location where they are being kept during the experiment. Students also had access the supplies used during the experiment (to complete the Materials section of their lab reports) and were also encouraged to edit their Procedures as needed. Finally, students had access to the class computers and were encouraged to begin writing out the Materials and Procedure sections of their lab reports.
Note: I conferenced with students identified as being in danger of failing (currently holding a D or an F in biology for the semester). I explained how each student could improve their grade and earn credit. Students then signed and returned copy of the Notification of Failing Grade / Action Plan form, and took another copy home to be signed by a parent. Signed forms must be returned by Monday, January 12.
Today, we focused on identifying the experimental data to include in the Results section of the Baggie Garden Experiment lab report. We compared the pros and cons of collecting lots of data with collecting a focused amount of data. Students identified, discussed, and justified which experimental endpoints they wanted to collect for their experiment, and then created data tables in their lab notebooks to collect the data. Finally, students made their first careful observations of their baggie gardens and recorded their observations. The slide deck includes lesson content, including a link to the Chia Pet video which is also available below.
Students conducted their Baggie Garden experiments today, setting up their experiment bags and one or more experimental control bags. We began class with a brief overview of the day, and then students worked alone or in pairs to write a high-level experimental procedure. Once their procedure was reviewed and teacher-approved, the students assembled their baggie gardens, using the resources available to test their hypotheses. After setting up the gardens, students were prompted to respond in their lab notebooks to the following questions:
- Measured Experimental Outcome:
- How will you collect your results?
- Where will your result be documented?
- How will you analyze your results?
- How will you interpret your results?
Tomorrow we will make our first experimental observations and then discuss how to organize how to collect and organize data relevant to each group’s research question.
Happy New Year! Hard to believe we are only three weeks away from the end of first semester! Before Winter Break, we began our study of cellular respiration and briefly touched on photosynthesis. Today we began studying plant biology by identifying testable experimental variables associated with plant seed germination. Tomorrow, students will establish baggie gardens in order to test whether their selected variable impacts seed germination and/or seedling growth. Our collective data will enable us to make detailed scientific observations and conclusions about factors affecting seed germination, seedling growth, and photosynthesis. Along the way, students will practice the art of inquiry by:
- identifying variables (manipulated, responding, and controlled)
- writing hypothesis statements (using the if…then…because… format)
- writing a detailed experimental procedure (incorporating the concepts of validity, reliability, repeated trials, and experimental control conditions)
- recording, organizing, and analyzing detailed observations
- writing a conclusion statement
Students will be expected to produce a typed lab report which includes a data table and a graph of the data.