Question

microscope mysteries
jennifer carefully placed her amoeba slide on the stage, under the stage clips. then she proceeded to focus the microscope under low and then under high power. when she was finished, she noticed that the slide was cracked. she did not drop the slide. how did it crack? select all answers that apply.
(there are 3 correct answers.)

□ she used the coarse adjustment knob while viewing under high power and the high power objective hit the slide and cracked it.

□ she used the fine adjustment knob while viewing under high power and the high power objective hit the slide and cracked it.

□ she did not focus the microscope under intermediate and switched to high power, the high power lens scraped the slide when moving the nosepiece.

□ she took the slide out of the microscope without moving the body upward.

Explanation:

1. First Option: When using high power, the coarse adjustment knob moves the stage (or objective) more drastically. Using it can cause the high - power objective to hit the slide, leading to cracking.
2. Third Option: If you don't focus at intermediate power and switch to high power, the high - power lens may be too close to the slide. When moving the nosepiece (to switch objectives), the lens can scrape the slide, causing it to crack.
3. Fourth Option: If the body (with the objective) is not moved upward when taking out the slide, the objective can still be close to the slide, and as the slide is removed, it can get cracked by the objective.

The second option is incorrect because the fine adjustment knob is for fine - tuning the focus and moves the stage/objective in small increments, so it is unlikely to cause the objective to hit the slide hard enough to crack it.

Answer:

• She used the coarse adjustment knob while viewing under high power and the high power objective hit the slide and cracked it.
• She did not focus the microscope under intermediate and switched to high power, the high power lens scraped the slide when moving the nosepiece.
• She took the slide out of the microscope without moving the body upward.