A student has to focus his compound microscope to observe a prepared slide showing different stages of binary fission in Amoeba. The steps he is likely to follow are listed below in a haphazard manner : 1. Adjust the diaphragm and the mirror of the microscope so that sufficient light may enter to illuminate the slide. 2. Fix the slide on the stage carefully. 3. Adjust the microscope to high power and focus. 4. Adjust the microscope to low power and focus. The correct sequence of the above steps to observe the slide under the microscope is

A student has to focus his compound microscope to observe a prepa…

MCQ

A student has to focus his compound microscope to observe a prepared slide showing different stages of binary fission in Amoeba. The steps he is likely to follow are listed below in a haphazard manner :

Adjust the diaphragm and the mirror of the microscope so that sufficient light may enter to illuminate the slide.
Fix the slide on the stage carefully.
Adjust the microscope to high power and focus.
Adjust the microscope to low power and focus.

The correct sequence of the above steps to observe the slide under the microscope is

A
$\ce{I, II, IV, III}$
✓
$\ce{II, I, IV, III}$
C
$\ce{II, IV, I, III}$
D
$\ce{I, IV, II, III}$

✓

Answer

Correct option: B.

$\ce{II, I, IV, III}$

First of all we place the slide on the stage and look through the eye piece and then adjust the mirror and diaphragm to get even illumination. Then, we look through the eye piece and move the slide until the object is visible. Again look through the eye piece and raise the objective using coarse adjustment until the object is focused. At last make the focus sharp with the help of fine adjustment.