Lab 3 Human A&P

You are observing the letter "e" under a compound microscope. Which of the following indicates how the image appears as you view it through the ocular lens?

ə

If your ocular lens is 10×, and you are using your 45× objective lens to view a slide, the total magnification is ________.

450×

How could you best improve the contrast of this specimen?

Open or close the iris diaphragm.

Which of the following sentences regarding microscope care and handling is correct?

Use the coarse adjustment knob only with the lowest-power objective.

The ________ is a substage lens that concentrates light on the specimen.

condenser

As total magnification increases, the depth of field ________.

decreases

As you increase the total magnification of the specimen, the size of the field ________.

decreases

As you increase the total magnification of the specimen, the working distance ________.

decreases

This is the formula for calculating the diameter of an unknown microscope field.

diameter of field A × total magnification of field A = diameter of field B × total magnification of field B Submit

You should always begin observation of specimens with the oil immersion lens.

false

When using the higher power objective lenses, you would use this part of the microscope to focus the specimen.

fine adjustment knob Submit

When observing a slide under a microscope, begin focusing with the ________-power objective lens in place.

lowest

You begin your observations using the ________ lens and the ________ adjustment knob.

lowest-power, coarse

The working distance for a 10× objective lens is ________.

much greater than the working distance for the 100× objective lens

The ________ of the microscope carries three or four objective lenses.

nosepiece

You prepare a wet mount of your own cheek cells and place it under the microscope, but find that you cannot see any detail of the cells. What can you do to make details more visible?

prepare another slide and stain with methylene blue

The ability to discriminate two close objects as separate is called ________.

resolution (or resolving power)

Before putting away the microscope in the storage cabinet you must observe all of the following except ________.

rotate the highest power objective lens in position

The microscope slide rests on the __________ while being viewed.

stage

When you want to study a slide under the microscope, you place it on the ________.

stage

Your lab microscope is parfocal. This means that __________.

the slide should be almost in focus when changing to higher magnifications

To transport a microscope, hold it ________.

upright, with one hand on its arm and the other hand supporting its base

How do you clean the lenses of your microscope?

with special lens paper and cleaner

You are looking at a slide of three crossed threads. Yellow is on the bottom, blue is in the middle, and red is on the top. When you rotate the adjustment knob forward (away from you) on your microscope, the stage rises. You move the adjustment knob to focus on the middle thread. As you rotate the adjustment knob forward, which color thread will come into focus next?

yellow