Exercise 3 - eScience Labs

[Pages:2]Exercise 3 Virtual Microscope

Experiment Inventory

Materials

Virtual Microscope on Student Portal *Computer *Internet Access

Labware

None Required

Note: You must provide the materials listed in *red.

EXPERIMENT 3: VIRTUAL MICROSCOPE

Microscopes are used across the field of forensics. From observing cell specimens to comparing fracture patterns on glass, microscopes help forensic scientists see minute, but important, details on crime scene evidence. While there are different types of microscopes, most have common structures and function in a similar way. In this exercise, you will practice using a virtual compound light microscope to observe specimens at varying magnifications.

Note: Review the directions for signing in to the Student Portal at the beginning of this manual if uncertain how to access this information.

PROCEDURE

1. Log into your eScience Labs Student Portal account and locate the Virtual Microscope activity located in the Evidence and Crime Scene section.

2. Take a tour of the virtual microscope by clicking the "Start Tour" button on the right hand side of the screen and learn how to use the different controls to effectively use the simulation.

3. Once you are comfortable using the virtual microscope, switch views so that you are looking at the microscope. 4. Select the "letter e" slide in the top right corner of the page. 5. Manipulate the stage until the letter e is positioned over the light source. 6. If the microscope light is off, turn it on. 7. Switch views so that you are looking through the ocular lens and at the slide. 8. Move the oculars until your field of view becomes a complete circle. 9. Use the 4X objective lens, coarse adjustment knob, and the fine adjustment knob until you can clearly observe the letter e

in the field of view.

Hint: This is achieved when a red circle appears over the letter e.

10. Manipulate the stage to move the letter e to the measurement line in the center of the field of view.

11. Rotate the objective lens to the next power and find a clear image of the letter e. 12. Repeat Steps 10 and 11 until the letter e no longer fits in the field of view. Observe at what magnification this occurs. 13. Switch views so that you are looking at the microscope. 14. Remove the letter e slide and select the cheek smear slide on the right side of the page. 15. Manipulate the stage so that the sample is over the light source. 16. Switch views and bring the cells within the red circle into focus using the 4X, then 10X, objective lenses. Use what you know

about operating a microscope to do this. 17. View the slide under the 40X and 100X objective lenses. 18. On the left hand side of the screen, select the "Try This" box. Under measurement, select the m1 box to open an activity that

will instruct you how to measure the letter e. Observe the height of the letter.

Note: If the software freezes after clicking the "Try This" button, refresh your browser and start again. You will have to go through the tutorial tour again in order for the "Try This" box to become available.

 ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download