THE MICROSCOPE LAB - Lab Homework (Please complete before you take quiz
Arrange the following steps of applying immersion oil in the correct sequence.
1) Focus on the specimen using the 40x objective lens. 2) Turn the objectives to half way between the 40x lens and the 100x lens. 3) Apply a drop of immersion oil directly onto area of the slide you were viewing. 4) Rotate the 100x lens over the microscope slide, and use the fine focus adjustment knob to sharpen the image.
Indicate the correct order of steps as you bring an object into focus under high power.
1) Place slide on stage and secure with stage clips. 2) Turn on the light and center the specimen over the light source. 3) Focus specimen on scanning objective using coarse focus adjustment 4) Rotate to low power objective, then use fine focus to sharpen the image 5) Rotate high power lens into position. 6) Readjust fine focus under high power to produce the sharpest image.
Which objective lens requires oil to be applied?
100x
The magnification of the ocular lens is
10x.
What lens could get dirty with oil if you move the revolving nosepiece in the wrong direction after viewing under oil immersion?
40x
You have successfully focused on an object with the 10x and 40x objective lenses. You have rotated the 100x objective lens into position but are unable to obtain a sharp image by rotating the fine focus adjustment knob. Which of the following is most likely to correct this problem?
Add a drop of immersion oil before rotating the 100x lens into position.
A wet mount requires the addition of certain dyes and cell fixatives approximately 12 hours before viewing the specimen.
False
The total magnification achieved using a 10× objective lens with a 10× eyepiece lens is 20×.
False
Label the image of a compound light microscope using the terms provided.sni
Link to Answer: https://imgur.com/dJsN7Xa
Complete the calculations for total magnification produced by various combinations of the eyepiece and objective lenses. Remember, to calculate the total magnification achieved when using a particular objective, multiply the power of the eyepiece by the power of the objective used.
When the scanning (4x) objective is used the total magnification will be 40x. When the low power (10x) objective is used the total magnification will be 100x. When the high power (40x) objective is used the total magnification will be 400x. When the oil immersion (100x) objective is used the total magnification will be 1000x.
When preparing a wet mount specimen for viewing, the specimen should be covered with
a coverslip.
The mechanical stage upper knob causes the stage to move
back and forth.
The __________ causes the stage to move upward or downward.
coarse adjustment knob
The fine adjustment knob on the microscope
fine-tunes the focus.
The coarse adjustment knob on the microscope
locates the focus plane.
A change in what component of microscopy influences the apparent size of the objects being viewed?
magnification
What does the term motile mean?
movable
Which objective lens provides the highest total magnification?
oil immersion
Using oil immersion is useful because
oil immersion increases the resolving power of the specimen.
The mechanical stage lower knob causes the stage to move
right and left.
The objective lenses of the compound light microscope are attached to the
rotating nosepiece.
Which objective lens provides the least total magnification?
scanning
What is the advantage of using a wet mount?
☑ The motility of a specimen can be viewed under a microscope. ☐ The wet mount is a safer way to view pathogenic organisms. ☑ The specimen can be viewed as living cells. ☐ The contrast of a specimen is enhanced with the addition of water to the slide.
Pond water can contain many types of organisms. Which of the following are you most likely to find in a pond water sample? Please select all that apply.
☑ bacteria ☑ algae ☑ rotifers ☐ human cells ☑ protozoa ☐ virus
Which of the following items will you need to make a wet mount?
☑ transfer pipette ☑ clean slide ☐ Bunsen burner ☐ timer ☑ tweezers ☑ cover slip
