What We Don't See

Objectives:
The learner will:
• Identify plant parts and their purposes.
• Use microscopic (or digital photo) technology to observe plant parts.
• Capture still images of plant parts.
• Create a digital slideshow of microscopic (or digital photo) observations.

Standards:
Based on Alabama Course of Study 2005 3rd Grade Science Standards
• 7 – Describe the life cycle of plants including seed, growth and reproduction
Based on Alabama Course of Study 2009 3-5 Grade Technology Standards
• 1 – Use input and output devices of technology systems
• 8 – Collect information from a variety of digital sources
• 12 – Create a product using digital tools

Materials:
• Laptop with internet connection (for the teacher)
• LCD projector and board (Smart Board if possible)
• Document Camera
• Living, or recently living, flowering plant with a long stem
• ProScope HR handheld miscroscope with 10x and 50x lens units.
o If no ProScope is available, you can choose to take digital pictures of the plant parts beforehand with similar zoom specifications.
• USB drives, one for each group
• Laptops for student use, one for each group

Engaging Question: How do plants absorb water from the soil?

Develop the Concept:
1. Use the website http://www.mbgnet.net/bioplants/parts.html to review the parts of the plant and each part’s purpose:
• Root – holds the plant in the ground and absorbs nutrients
• Stem – carries water and nutrients to other parts of the plant
• Leaf – absorbs sunlight and makes food for the plant
• Flower – produces materials to create new plants

2. After the parts of the plant have been reviewed, place the flowering plant under the lens of the document camera so that students can observe the plant as a whole. Have groups discuss what physical attributes they notice about each part – the size, shape, color, etc.

3. Discuss how plants initially obtain water from the ground. Students should understand that the roots are the first part of the plant to activate this process. Using the Proscope HR with the 10x lens attached, observe the roots of the plant more closely. (If no Proscope is available, use a digital picture taken with a moderate zoom focus). Hold the Proscope as closely as possible to the roots and adjust the lens as needed. Do students notice things about the roots that they did not notice with the document camera lens? Groups should record these observations in their Science journals. Take still images of the roots using the Proscope HR. Demonstrate to students how to capture these images.

4. Attach the 50x lens to the Proscope HR (or use a digital picture with the closest zoom focus possible that also maintains high resolution) and observe the roots again. Students should record any new observations in their Science journals. Have a volunteer capture a still image of the roots using the Proscope HR.

5. Have students discuss which part of the plant receives water from the roots – the stem. Using first the 10x then the 50x lens (or digital pictures), observe the stem. Students should discuss their observations with their group and record in their Science journals. Have volunteers capture still images of the stem using the Proscope HR.

6. For the last observation, cut the stem into five pieces and give one piece of the stem to each group. As groups continue to observe their stem with the naked eye, one group at a time may come to the Proscope HR and use it to observe the inside of the stem. They should be able to observe “tunnels” that run the length of the stem. Students should take still images of these “tunnels” using the Proscope HR. After returning to their desks, each group should draw a picture of their observations and discuss how these observations help answer the question, how do plants absorb water from the soil?

Culminating Activities:
1. As groups are discussing their findings, save the Proscope still images to USB drives for each group and distribute the USB drives to the groups.

2. Students should work in their groups to create a Google Presentations slideshow of the still images. The students should insert one photo from each Proscope observation and include text. The text should come from the observation notes taken throughout the lesson.

3. Students present their slideshow to the class and discuss their observations.