Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
31 Cards in this Set
- Front
- Back
Exercise 4
|
The Microscope
|
|
Part A
|
Care and Use of the Compound Microscope
|
|
Handling Microscope
|
1. Always carry the microscope upright with two hands: one hand on the base, and one hand on the arm. 2. Make sure your workbench is free of clutter before you place the microscope on the bench. 3. Do not drag or shove the microscope across the lab. 4. Always lift the microscope to move or turn it.
|
|
Preparing Microscope for Storage
|
1. The scanning objective lens is in position above the stage aperture. 2. The mechanical stage has been positioned so that the stage arm is flush with the right side of the stage. 3. The cord is wrapped around the holder and secured. 4. The stage has been adjusted to midpoint.
|
|
Part B
|
Magnification
|
|
Total Magnification
|
Magnification of the Ocular lens (10x) X Magnification of the Objective lens
|
|
Three Objective Lenses
|
Scanning 4x
Low Power 10x High Dry Power 40x |
|
Part C
|
Working Distance and Diameter of the Field of View
|
|
Part C-1
|
Working Distance
|
|
Working Distance
|
The distance between the stage and the objective lens. As magnification increases; it decreases.
|
|
Part C-2
|
Diameter of the Field of View
|
|
Field of View
|
The extent of the visible image field that can be seen.
|
|
Formula for Calculating Diameter of Field of View
|
M1 X DFV1 = M2 X DFV2
|
|
Diameter of the Field of View
|
As magnification increases; it decreases.
|
|
Part D
|
Estimation of Cell Size
|
|
Size of Cell
|
= DFV/# of cells to fill the DFV
|
|
Part E
|
Preparation of Wet Mounts and Replacement Staining
|
|
Procedure for Creating Wet Mount
|
1. Obtain a clean glass slide and coverslip.
2. Place one or two drops of water on the slide. 3. Obtain specimen and prepare as needed. 4. Place specimen in water. 5. Carefully position the coverslip by placeing one edge of it down first and then lowering the other side. Try to minimize the number of air bubbles that form. 6. The coverslip should not be floating on the slide. If it does, remove the coverslip and excess water and start over. |
|
Part E-2
|
Onion Epidermis
|
|
Procedure for Replacement Staining Technique
|
1. Place a few drops of IKI on the slide against one edge of the coverslip.
2. Place the smooth edge of a single layer of paper towel up against the opposite edge of the coverslip. The paper towel will pull the water out from under the coverslip and the stain (IKI) will replace the water. 3. Continue the process, adding more IKI if necessary, until the stain covers the area under the coverslip. 4. Wait a few minutes and then place distilled water on one side of the coverslip and draw the excess IKI out with the paper towel. The water then replaces the IKI. 5. Once all the yellow IKI has been removed, dry the upper surfaces of the slide. |
|
Part E-3
|
Cheek Cells
|
|
Nucleus
|
The chromosome containing organelle of a eukaryotic cell.
|
|
Cytoplasm
|
The contents of the cell, exclusive of the nucleus and bounded by the plasma membrane.
|
|
Plasma Membrane
(Cell Membrane) |
The cell’s outer membrane made up of a two layers of phospholipids with embedded proteins. It separates the contents of the cell from its outside environment, and it regulates what enters and exits the cell.
|
|
Part E-4
|
Pond Water
|
|
Techniques for Viewing Living Microorganisms
|
Staining techniques will kill the specimen. Can add Protoslo to wet mount to slow movement of microorganism.
|
|
Part F
|
The Dissecting Microscope
|
|
Dissecting Microscope
|
Lower magnification used for larger specimens. As magnification increases, DFV increases.
|
|
Part G
|
Use of a Dichotomous Key
|
|
Dichotomous Key
|
A reference tool where a series of choices between alternative characters leads progressively to the identification of the species.
|
|
Procedure for Using Dichotomous Key
|
1. Obtain specimen.
2. Examine using microscope. 3. Use the dichotomous key provided to decide which order your specimen belongs in. 4. Begin with couplet 1 and determine which of the two statements more closely fits your specimen. 5. When you have decided which of the two statements applies to your specimen, move to the couplet pair that is listed at the end of that statement. 6. Determine which of the two statements again more closely fits your specimen. 7. Continue to work your way through the key, deciding between pairs of statements, until you arrive at a name. |