Reading...
Play button
Play button
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;
11 Cards in this Set
- Front
- Back
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the OBJECTIVE? |
The objective lenses - A microscope will usually have three or four objective lenses mounted on a revolving nose piece. Most microscopes have objective lenses that magnify and object 4X (scanning), 10X (low-power), 40X(high-dry), and 100X (oil immersion). List the magnification powers of the objective lenses on your microscope. As the barrel of the objective lens increases inlength, the magnifying power also increases.
|
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the STAGE? |
BIO 141 - Lab Exam 1
The STAGE - The flat platform located beneath the objective lenses on which the microscope slide is placed. The stage has a hole in the middle, the light aperture, through which light is focused on the slide. The slide may be held onto the stage with either two spring clips or a mechanical stage clamp. Does your microscope have 2 spring clips or a mechanical stage? |
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the DIAPHRAGM LEVER (under condenser) |
Iris diaphragm: located beneath the condenser, the iris diaphragm works similarly to the iris of the eye. By adjusting its LEVER, the aperture changes diameter and regulates the amount of light that passes through the condenser. Decreasing the aperture size decreases the amount of light on the specimen and increases contrast.
|
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the CONDENSER? |
Condenser: Located just below the stage is a lens that condenses light through the specimen on the slide above. If the condenser has an ADJUSTMENT KNOB that raises and lowers the condenser, it usually needs to be in the highest position to focus the most light on the specimen.
|
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the SUBSTAGE LIGHT / light source? |
Substage light - The light source is usually built into the base of the microscope and typically has a dial or sliding bar on one side to control the light intensity.
|
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the COARSE FOCUS KNOBS (coarse adjustment knob) ? |
On each side of the microscope toward the base is a large knob ob dial that may or may not have a smaller knob in the middle.
Only one of the large knobs needs to be used, depending on whether one is right- or left-handed. The large knob is used for coarse focusing and either moves the stage up and down quickly or moves the objective lenses up and down quickly. This knob is to be used with scanning or low-power lenses. Does your stage or objective lens move? |
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the FINE ADJUSTMENT KNOB (fine focus knob)? |
FINE FOCUS KNOB (fine adjustment knob): The smaller knob on each side of the microscope that is used for precision focusing.
|
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the MECHANICAL STAGE? |
MECHANICAL STAGE - holds the slide securely in place with a spring clamp for viewing and can be moved with precision by using the ADJUSTER KNOBS. One knob moves the slide side to side, and the other forward and backward.
|
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the BASE? |
BASE - the wide bottom part that supports the microscope.
|
|
Compound Microscope:
Where is and which function has the ARM? |
ARM - the straight or curved vertical part that connects the base to the head.
|
|
BIO 141 - Lab Exam
Compound Microscope: Where is and which function has the HEAD? |
HEAD - or body tube - the upper part of the microscope that extends from the arm and contains the ocular lens(es) and the rotating nosepiece with the objective lenses.
|
