Make sure you know how to make conversions within the metric system. If you'd like to review, see Bregman's manual (inside front cover) for table of linear measurements frequently used by cell biologists. Also, try this link: metric system. See only first page of site. Be sure you can convert from micrometers to mm. Hint: One micrometer is 10-3mm.
Review the parts of the microscope, Bregman, Fig. 1.1.
Here are some sites your may find interesting:
Elodea sp. - notice that this plant which you yourself may have grown in a fish tank is a flowering plant!
Follow up questions about the lab - practice making measurements at the microscopic level!
Click to see a "protoplast" of Nitella (it's the "4th micrograph on their page). Measure the size of the protoplast by referring to the 0.3 mm bar. Calibrate your ruler by comparing it to the bar for most accurate measurements.
Click on the micrographs of leucocytes in the Loyola University Medical School's LUMEN Website and answer the following questions:
Click on Figure 51 - and, using a red blood cell (erythrocyte) for reference, calculate the size of the white blood cell or leucocyte. HINT: (A red blood cell in a smear is approximately 7.5 micrometers in diameter. Use a ruler to get precise dimensions. Note: If you are interested in Medicine, the Loyola University Medical School's LUMEN Website provides a wealth of information including many excellent histology and anatomy images.
Go to Figure 52. If the Plate magnification of the micrograph is 3333x, what is the diameter of the eosinophil?
Figures 57-64 are EM's (electron micrographs) of a number of different leucocyte types. Click on Figure 58. What is the plate magnification of Figure 58 if the actual diameter of the eosinophil in the field is 16 micrometers?