1. The Microscope . . . Taking a look at the structure of the cell.
Lesson Objectives:
1. Be able to state three things the Cell Theory has lead
2. Be able to identify the different parts of a Microscope
3. Be able to effectively use a microscope to view and draw specimen using proper scientific diagram technique.

2. Early microscopes allowed scientists to discover the cell
Early microscopes allowed scientists to discover the cell. Modern microscopes are so powerful that scientists are able to discover how cells work.
Before the invention of the earliest microscope, people believed life could arise from spontaneous generation.
But more on this tomorrow…

3. What has the cell theory led to?
Sophisticated microscopes have allowed scientists to discover a great deal about the structure and function of cells. In the 21st century…
They can treat many diseases. Ex. Leprosy, cancer, tetanus, AIDS
They can graft new or artificial skin to replace the destroyed skin of burn patients.

4. They can transplant whole organs into patients with organ failure (e.g. heart, liver, kidney)

5. They can turn one cell into anther type of cell to treat disease like osteoporosis and Parkinson’s disease
i.e., Stem Cells

6. Labs examine cells, tissues and body fluids to detect disease in people and animals
Ensure our food and water are safe

7. Video interlude… Why are cells important?
Uses of “Model Skin”
Burn treatment

8. Microscope Activity

9. Procedure for Using the Microscope
1. The microscope is carried by placing one hand on the arm and the other hand under the base.
2. Always begin your observations by bringing your specimen into focus with the coarse adjustment knob. Adjust the diaphragm so that the field of view is brightly light. With the low power objective in position and the diaphragm in position, raise the stage using the coarse adjustment until the specimen comes into view. Now gradually focus the low power objective by turning the coarse adjustment knob until the specimen comes into focus.

10. 3. To bring your specimen into sharper focus, you may turn the fine adjustment knob. 4. To switch to a higher power, center the part of the specimen which you wish to observe, then switch to the higher power objective by moving the revolving nosepiece. You can sharpen the image by turning the fine adjustment knob. You should NEVER use the coarse adjustment to bring the specimen on focus under medium or high power objectives. 5. If your field of view is too dark or too bright, you may adjust this brightness by adjusting the diaphragm located under the stage.

11. 6. When you have completed your observations, check to make certain the low power objective is in position above the stage before returning the microscope to storage. Lower the stage to its lowest level.
7. Wrap the power cord around the base. Return the microscope to its proper location.

12. PROCEDURE FOR BIOLOGICAL DRAWINGS
1. Draw only what you see.
2. Use a pencil for all drawings and labels.
3. Keep your drawing large enough to show all structures without crowding.

13. 4. Locate the drawing to the left of centre.
5. Labels are located in a column to the right of centre.
6. Label lines are drawn with a ruler.
7. The title is underlined and located to the left of the diagram.
8. The value for the magnification is located in the bottom right hand corner.

14. Example (You don’t need to draw the field of view!!)

15. Your Task
Microscope Functions Table

16. The Microscope: Preparing a Wet Mount- Part I
Objectives:
1. Successfully prepare a wet mount of a typical plant cell
2. Draw and label a proper scientific diagram of a typical plant cell

17. Cell Investigations
1) Prepare WET MOUNT slides of the cell type below. NOTE: Your teacher will show you how to make a wet mount slide as well as how to gather these cell types.
a. onion epidermal cell
plant leaf cell
human cheek cell

18. 2). Closely investigate each cell type using the microscopes provided
2) Closely investigate each cell type using the microscopes provided. Take your time and be observant. ASK if you need any help.
3) Draw a sketch of each cell type in your notebook. The sketch should be drawn in pencil, have a date, a title, and be large enough to show detail (one per page). Take care to be as neat as possible.

19. *Note: For any formal microscope drawings, ALWAYS:
 Use a sharp PENCIL
 NEVER use a pen or colour
 Label all known parts with a ruler (to right side of drawing)
 Place only one diagram per page
 Be as neat and accurate as possible
 Use unlined paper
 Provide a title
 Stipple (no shading)
 List stain type (if any) and magnification (ocular x objective magnification)

20. PREPARING A WET MOUNT 1. Clean the slide and cover slip.
2. Add a drop of water to the slide.
3. Add your specimen to the drop of water.
4. Holding the cover slip with your thumb and forefinger at a 45° angle, place the edge of the coverslip at one end of the specimen and slowly lower the coverslip onto the slide to allow air to escape. Air bubbles will interfere with viewing the sample!

21. 5. To add a stain, place a few drops of the stain at one edge of the cover slip.
6. To draw the stain under the cover slide, place a piece of paper towel at the other end of the cover slip.
7. Remove the paper towel once the stain has completely covered the specimen.

22. 8. Draw a diagram of only one cell. Only draw what you can see.
9. Repeat steps 1-8 for the plant leaf cell. Try to label all the structures you see. (Ask me for help!)

23. What do you need to produce.
Today
2 Diagrams (One page per paper.)
1 properly drawn and labelled scientific diagram of an onion cell
1 properly drawn and labelled scientific diagram of a plant cell
Ensure that each diagram has an appropriate label at the top left hand corner and the magnification at the bottom right hand corner of the paper.
Hand in diagrams for me to mark!!!!

24. Your Task 1. Answer discussion question for the onion cell.
2. List at least 3 similarities and differences between the plant leaf cell and the onion cell.

25. The Microscope: Preparing a Wet Mount- Part II
Objectives:
1. Successfully prepare a wet mount of a typical animal cell
2. Draw and label a proper scientific diagram of a typical animal cell

26. What you must produce…
One properly drawn and labelled diagram of your cheek cell.
YOUR TASK!
1. Answer the discussion questions provided.