Activity 12: The Cells of Plants

Transcription

1 Name Activity 12: The Cells of Plants Guiding Question: What structures in plant cells convert energy from the sun into energy stored in food? Key Words: cell, cell wall, chloroplast, energy Get Started: 1. Why do we need plants? 2. Since humans and other animals eat plants, what do plants eat? Plants are called producers because they make (produce) their own food. A common misconception is that producers are making food for other organisms that eat the plants. This is not the case. The producers are making food for themselves. 3. Read the introduction and Guiding Question to Activity 12, The Cells of Plants in your Student Book. 4. Look at Visual Aid 12.1, Plant Photosynthesis, which is attached to this packet. Plants use the energy from the sun to create sugars, or food. In this process, called photosynthesis, plants use water and carbon dioxide and release oxygen. The sugars are stored within the cells and broken down during cellular respiration when the plants need energy. The carbon in sugars, which comes from the carbon in carbon dioxide, is the building block for sugars, amino acids, and fatty acids discussed in the previous activity. 5. How does the plant get water from the soil to the leaves? How does the plant get enough sunlight?

2 Name Do the Activity: 1. Read procedure steps 1-6. Watch the LABsent video (found here: LABsent Cells 12), to view the experiment being done. Each time the video says to record, you may want to pause the video to give you ample time to complete your observations. Procedure step 5: Draw your observations of several cells from each plant on Student Sheet 3.1, Microscopy Drawings, which is attached to this packet. Be sure to record the type of plant and the level of magnification. Include details inside the cell and along the edge of the cell membrane on your drawing. Build Understanding: 1. All four of the slides you observed were of producers. How did the cells of the producers vary? 2. Did you observe little green ovals or circles? In which cells did you observe these organelles? 3. These green ovals or circles are chloroplasts and are green because they contain chlorophyll, the molecule that enables such cells to absorb the energy available from sunlight. In which parts of the plant is photosynthesis occurring?

3 Name 4. In this activity, you viewed the crosscutting concept of energy and matter. In your Student Book, review the meaning for this crosscutting concept found in Appendix G. How does the crosscutting concept of energy and matter relate to this activity? Analysis: 1. Using various microscope techniques, scientists have identified the structures most commonly found in plant cells. Some of these structures are shown in the diagram of the plant cell (below). Not all plant cells contain every structure, though most plant cells do contain the majority of them. However, some of these structures are very difficult to observe if you use only a light microscope. a. Which cell structures were you able to observe? List them. b. Which cell structures were not visible to you? List them.

4 Name 2. Compare the various plant cells you observed. Which cell structures did all of the plant cells appear to have in common? What functions do these structures have in the cell? 3. Look at the simplified diagram of an animal cell shown below. Animal cells, as well as plant cells, contain many structures; this diagram shows only some of these structures. a. Compare the plant cell diagram with the animal cell diagram. Based on these diagrams, what

5 Name structures would you expect to find in both plant and animal cells? b. Based on your comparisons, which structure (or structures) within a plant cell do you think is most important in food production? 4. Plants make their own food. In the Energy and Matter in Cells activity, you learned that matter is neither created nor destroyed. Explain how plants obtain matter and use it to make their own food. Hint: Think about how the different parts of the plant, such as leaves and roots, interact with the environment.

6 Name 5. In 2010, scientists discovered the first microbe that infects both plants and people. The pepper mild mottle virus can be transmitted from plants to people, though it is not yet known whether the virus causes any symptoms (such as fever or itching) in people. Why do you think most microbes that infect plants do not infect people?

7 Name

8 Name