When focusing on a slide, ALWAYS start with either
the 4X or 10X objective
. Once you have the object in focus, then switch to the next higher power objective. Re-focus on the image and then switch to the next highest power.
Which objective lens should you always use first when viewing a new slide quizlet?
always focus first with the course adjustment and
the low-power objective lens
.
What objective should always be used first?
When using a microscope, you should always start with
the lowest power objective
when first viewing a specimen. Typically light microscopes have 4x, 10, 40x, and 100x objectives, therefore, you should start with the 4x objective.
Which objective lens is always used first when viewing a slide on the compound microscope quizlet?
Use
the lowest objective lens (4x)
to begin.
What is the total magnification of an object when viewed with the 4x objective lens of a microscope?
The same principle apply to stereo microscopes, a 10X eye piece combined with a 4X objective lens will produce
40X
magnification. Some stereo microscopes equipped with continues zoom objective lens with magnification from 0.75X – 7.5X. The total magnification will be 7.5X to 75X when combined with 10X ocular lens.
What is the best objective lens to search for an object with the microscope?
Since the
4x objective lens
has the least magnification, but a larger field of view, it allows for more of the specimen to be seen, as well as locating the part of the sample you wish to view. This in turn makes it easier to focus on the sample.
What is the first step normally taken when you look through the ocular lenses?
What is the first step normally taken when you look through the ocular lenses? The first step when looking through the ocular lenses is
adjusting the light and the objectives.
Which part of the microscope does the microscope slide rest on while being viewed?
Stage
: The platform the slide rests on while being viewed. The stage has a hole in it to permit light to pass through both it and the specimen. The mechanical stage permits precise movement of the specimen.
Is the flat surface that slides are placed for viewing?
Stage
: The flat platform where you place your slides. Stage clips hold the slides in place.
What is the sequence of objective lens from low to high power?
Magnification: Your microscope has 4 objective lenses:
Scanning (4x), Low (10x), High (40x), and Oil Immersion (100x)
. In this lab, you will not use the oil immersion lens; it is for viewing microorganisms and requires technical instructions not covered in this procedure.
What are the 3 objective lenses on a microscope?
Essentially, objective lenses can be categorized in to three main categories based on their magnification power. These include:
low magnification objectives (5x and 10x) intermediate magnification objectives (20x and 50x)
and high magnification objectives (100x).
When looking at a specimen on your slide you should always start with the?
When focusing on a slide, ALWAYS start with
either the 4X or 10X objective
. Once you have the object in focus, then switch to the next higher power objective. Re-focus on the image and then switch to the next highest power.
When looking through a compound microscope using a 10x ocular lens and a 4x objective lens What is the total magnification?
Light is passed through the sample (called transmitted light illumination). Larger objects need to be sliced to allow this to happen efficiently. Compound microscopes usually include exchangeable objective lenses with different magnifications (e.g 4x, 10x, 40x and
60x
), mounted on a turret, to adjust the magnification.
What is the first thing to do when using a microscope?
- Step 1: Moving Your Microscope. Carry the microscope with two hands. …
- Step 2: Microscope Lens Care. Never touch any lens with your fingers. …
- Step 3: Microscope Parts. …
- Step 4: Prepare a Slide. …
- Step 5: Insert the Slide. …
- Step 6: Set Up for Viewing. …
- Step 7: Light Control. …
- Step 8: Focus the Microscope.
When viewing the microscope What is the image of the specimen?
When you look into a microscope, you are not looking at the specimen, you are looking at the image of the specimen. The image appears to be
“floating” in space about 10 millimeters below the top of the observation tube
(at the level of the fixed diaphragm of the eyepiece) where the eyepiece is inserted.
What is the first step normally taken when you look through the ocular lenses quizlet?
1. What is the first step normally taken when you look through the ocular lenses?
To adjust the eye pieces to line up into the light circle correctly.
What is the first step you should take to focus the image on the slide?
what are the steps you should use to focus the image on the slide? examine the slide with the naked eye, begin on low power,
focus with the coarse focus knob
, then refine the focus with the fine adjustment knob.
On what part of the microscope are the objectives lenses located?
Nosepiece
: The upper part of a compound microscope that holds the objective lens. Also called a revolving nosepiece or turret.
Which statement best describes what the condenser does when viewing a specimen?
In a compound light microscope, what is the function of the condenser?
To concentrate light on the specimen
. Light diverges through the air as it exits the light source. The condenser gathers this divergent light and concentrates it on the specimen.
What part of the microscope moves the slide on the stage?
Stage clips hold the slides in place. If your microscope has a mechanical stage, you will be able to move the slide around by
turning two knobs
. One moves it left and right, the other moves it up and down. Usually you will find 3 or 4 objective lenses on a microscope.
What controls the movement of the slide on the stage?
MECHANICAL STAGE CONTROLS
— A geared device to move the slide (placed in the slide clamp) precisely. 4. COARSE ADJUSTMENT KNOB — A rapid control which allows for quick focusing by moving the objective lens or stage up and down. … OCULAR ADJUSTMENT — An adjustment for differences in the focusing abilities of your eyes.
Where the slide is placed for viewing?
| A B | BASE The bottom part of the microscope. | STAGE Part of the microscope that supports the slide that is being viewed. | COVER SLIP Name for the small plastic or glass piece that is used to cover a water drop on a slide. | SLIDE Small glass plate on which specimen are placed for viewing. |
|---|
What is the role of the objective lens?
The “objective lens” is
the first-stage lens to form an image using electrons exiting from the specimen
. The objective lens is the most important lens in the imaging lens system because the performance of this lens determines the image quality (resolution, contrast, etc).
What does the objective lens do on a light microscope?
The objective, located closest to the object,
relays a real image of the object to the eyepiece
. This part of the microscope is needed to produce the base magnification. The eyepiece, located closest to the eye or sensor, projects and magnifies this real image and yields a virtual image of the object.
When should you use the low power objective lens on the microscope?
Low power objectives cover a wide field of view and they are useful for
examining large specimens or surveying many smaller specimens
. This objective is useful for aligning the microscope. The power for the low objective is 10X.
Which of the following objective lenses is the low power lens?
A scanning objective lens
provides the lowest magnification power of all objective lenses. 4x is a common magnification for scanning objectives and, when combined with the magnification power of a 10x eyepiece lens, a 4x scanning objective lens gives a total magnification of 40x.
When the power of ocular lens is 10X and objective lens is 20x the magnification is?
For example, an objective lens of 20x and an ocular lens of 10x make the total magnification
200x
. A magnification of 1x refers to the status where an object is viewed with the eye from a distance of 250 mm.
What is the total magnification when using a 10X ocular lens and a 40X objective lens?
Each objective lens has a different magnification. Multiply the magnification of the eyepiece by the magnification of the objective lens to produce total magnification. For example, a 10X ocular lens and a 40X objective lens will produce a total magnification of
400X
(10 x 40 = 400).
What are the 4 objective lenses?
Objective Lenses: Usually you will find 3 or 4 objective lenses on a microscope. They almost always consist of
4x, 10x, 40x and 100x powers
. When coupled with a 10x (most common) eyepiece lens, total magnification is 40x (4x times 10x), 100x , 400x and 1000x.
When using the high power objective you should not use the?
Use the coarse focus to raise the stage all the way up until it blocks. The objective at the highest position, the 4x objective should of course
not touch the slide
.
When using an ocular lens with 10X magnification power which objective lens should be used to obtain the following actual magnification a 100 times of its diameter?
The objective and ocular lenses are responsible for magnifying the image of the specimen being viewed. So for 10X objective and 10X ocular, Total magnification =
10 X 10 = 100X
(this means that the image being viewed will appear to be 100 times its actual size).
How do you select an objective lens for viewing?
- 1, When the size of the measurement object is known. Since the field of view and spatial resolution are decided for each objective lens, select the objective lens referring to it. …
- Immersion…… …
- Coverslip correction…… …
- Long Working distance…… …
- For IR observation……
How do you use objective lenses?
Turn the revolving turret (2) so that the lowest power objective lens (eg. 4x) is clicked into position. Place the
microscope
slide on the stage (6) and fasten it with the stage clips. Look at the objective lens (3) and the stage from the side and turn the focus knob (4) so the stage moves upward.
What objective lens you should have in place to begin looking at your specimen explain why?
Why do you need to start with
4x
in magnification on a microscope? The 4x objective lens has the lowest power and, therefore the highest field of view. As a result, it is easier to locate the specimen on the slide than if you start with a higher power objective.
When looking through your microscope if you move your slide to the right the slide appears?
If you have to close one eye when looking into the microscope, it’s ok. Remember, everything is upside down and backwards. When you move the slide to the right,
the image goes to the left!
When looking to your microscope you move your slide to the right it appears?
A specimen that is right-side up and facing right on the microscope slide will appear
upside-down and facing left
when viewed through a microscope, and vice versa. Similarly, if the slide is moved left while looking through the microscope, it will appear to move right, and if moved down, it will seem to move up.
What part of the microscope changes the objective lens?
Revolving Nosepiece or Turret
: This is the part that holds two or more objective lenses and can be rotated to easily change power. Objective Lenses: Usually you will find 3 or 4 objective lenses on a microscope.
What should you do to the microscope after using before keeping it?
After using the microscope,
turn off the illuminator and wait for it to cool for several minutes
before putting it away. By allowing the bulb to cool you will extend its life. Also, make sure you do not store your microscope in an area that has corrosive chemical fumes that can destroy lenses or metal parts.
