Slide 1 / 21 Slide 2 / 21 New Jersey Center for Teaching and Learning BIOLOGY Progressive Science Initiative This material is made freely available at www.njctl.org and is intended for the non-commercial use of Animal & Plant Lab students and teachers. These materials may not be used for any commercial purpose without the written permission of the owners. NJCTL maintains its website for the convenience of teachers who wish to make their work available to other teachers, participate in a virtual professional learning Eukaryotes & Gene Expression community, and/or provide access to course materials to parents, students and others. www.njctl.org Click to go to website: www.njctl.org http:/ / njc.tl/ 16 http:/ / njc.tl/ 6 Slide 3 / 21 Slide 4 / 21 Purpose Materials Students will observe the differences between plant and animal Forceps cells. Medicine Droppers or plastic pipets Elodea plant or similar aquatic plant Water Compound Microscope Glass Slides Coverslips Toothpicks Methylene blue stain Paper Towels Lens paper Slide 5 / 21 Slide 6 / 21 Procedure A: Procedure A: Examining Plant Cells Examining Plant Cells Step 1 Obtain a microscope from the storage cabinet and place it Step 6 Using the low-power objective lens, locate the leaf under on your lab table. the microscope. Turn the coarse adjustment knob until the leaf comes into focus. Center the leaf in the field of view and observe Step 2 Place a drop of water in the center of a clean glass slide. the cells. Step 3 Using forceps, remove a leaf from the Elodea plant and Step 7 Switch to the medium-power objective lens. Locate the leaf place it on the drop of water on the slide. Make sure that the leaf using the microscope. Turn the fine adjustment knob until the leaf is flat. If it is folded, straighten it with the forceps. comes into focus. Do not turn too far in one direction. Center the Step 4 Place a coverslip over the drop of water and Elodea leaf. leaf in the field of view. Try not to get any bubbles trapped under the coverslip. Step 8 Switch to the high-power objective lens. CAUTION: When Step 5 Place the slide on the stage of the microscope with the leaf turning to the high-power objective lens, you should always look at directly over the opening in the stage. the objective from the side of your microscope so that the objective lens does not hit or damage the slide. Step 9 Observe the cells of the Elodea leaf. Draw and label what you see in the appropriate place in Data section . Record the magnification of the microscope. 10. Dispose of the coverslip and Elodea leaf. Wash and dry the glass slide so that it can be reused.
Slide 7 / 21 Slide 8 / 21 Procedure B: Procedure B: Examining Animal Cells Examining Animal Cells Step 1 Place a drop of water in the center of a clean glass slide. Step 6 To remove the stain from under the coverslip and replace it with clear water, place a piece of paper towel at the edge of one Step 2 Using the flat end of a toothpick, gently scrape the inside of side of the coverslip. Then place a drop of water at the edge of the your cheek. CAUTION: Do not use force when scraping the inside coverslip on the opposite side. The stained water under the of your cheek. Only a few cells are needed. The end of the toothpick coverslip will be absorbed by the paper towel. As the stain is will have several cheek cells stuck to it even though you may see removed, the clear water next to the coverslip on the opposite side will be drawn under the coverslip. Discard the paper towel after it nothing but a drop of saliva. has absorbed the stained water. Step 3 Stir the water on the slide with the end of the toothpick to mix Step 7 Place the slide on the stage of the microscope with the the cheek cells with the water. Dispose the toothpick in the trash center of the coverslip directly over the opening in the stage. container. Step 8 Using the low-power objective lens, locate a few cheek cells Step 4 Put one drop of methylene blue stain on top of the drop of under the microscope. Make sure they are centered in the field of water containing the cheek cells. CAUTION: Use care when working view. Note: You will need to reduce the amount of light coming with methylene blue to avoid staining hands and clothing. You may through the slide in order to see the cells more clearly. Adjust the want to wear gloves and an apron when performing this step diaphragm as necessary. Step 5 Wait one minute, then carefully place a coverslip over the stained cheek cells trying to avoid trapping any bubbles under it. Slide 9 / 21 Slide 10 / 21 Procedure B: Procedure B: Examining Animal Cells Examining Animal Cells Step 9 Switch to the medium-power objective lens and locate a cell Step 12 Dispose of your coverslip in the trash container. Wash, rinse, under the microscope. Turn the fine adjustment knob until the cell and dry your glass slide for reuse. comes into focus. Do not turn too far in one direction. Center the cell in the field of view. Step 13 Return your microscope to the storage cabinet. Make sure not to leave any slides on the microscope stage. Make sure the low- Step 10 Switch to the high-power objective lens. CAUTION: When power objective is in place before storing your microscope. turning to the high-power objective lens, you should always look at the objective from the side of your microscope so that the objective lens does not hit or damage the slide. Step 11 Observe some cheek cells. Draw and label what you see in the appropriate place in Data section . Record the magnification of the microscope. Slide 11 / 21 Slide 12 / 21 Data Animal v. Plant Lab Draw your observations of plant and animal cells here. Label each Analysis drawing as either a plant cell or animal cell and include the magnification. Grade: «grade» Subject: «subject» Date: «date»
Slide 13 / 21 Slide 14 / 21 1 What is the shape of an Elodea cell? 2 What is the general location of the nucleus in an Elodea cell? Students type their answers here Students type their answers here Slide 15 / 21 Slide 16 / 21 3 What is the shape of the cheek cell? 4 What is the general location of the nucleus in a cheek cell? Students type their answers here Students type their answers here Slide 17 / 21 Slide 18 / 21 5 How are plant and animal cells similar in structure? 6 How are plant and animal cells different in structure? Students type their answers here Students type their answers here
Slide 19 / 21 Slide 20 / 21 7 Why are stains such as methylene blue used when observing cells 8 In general, the surface of a tree has a harder "feel" than does the under the microscope? surface of your skin. What cell characteristic of each organism can Students type their answers here be used to explain this difference? Students type their answers here Slide 21 / 21 9 If you were given a slide containing living cells of an unknown organism, how would you identify the cells as either plant or animal? Students type their answers here
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