Microscope, Staining and Wet Mounts

In preparing a slide, why the specimen is stained?

• To make the cells bigger

• To separate the cells

• To make the specimen more colourful

• To make the structures easier to be seen

In preparing temporary mounts for microscopic examination, why the specimen has to be thin?

• To make the specimen easier to be focused

• To make the specimen easier to be covered by the cover slip

• To reduce the amount of stain used

• To allow light pass through the specimen to the objective

It is difficult to see the nuclei of cells under light microscope. Which of the following would help to make the nuclei more visible?

• staining the cells before mounting.

• using a thinner glass slide for mounting the cells.

• increasing the illumination of the cells.

• reducing the distance between the cells and the objective lens.

The following diagram shows the technique in lowering the cover slip to cover the specimen. Why must the edge of the cover slip touch the stain before it is lowered?

• To make sure the stain spread out evenly.

• To protect the specimen from breaking into pieces.

• To keep the temporary mount tidy for observation under a microscope.

• To avoid the formation of air bubbles under the cover slip.

A student examines the epidermis of a leaf under the microscope. In order to observe more cells within the field of view, he should

• increase the illumination of the slide.

• decrease the illumination of the slide.

• use an objective with a lower magnification.

• use an objective with a higher magnification.

Which of the following statements about observation under a microscope is correct?

• Under low power magnification, the area of specimen observed is larger.

• Under low power magnification, a more detailed image is observed.

• Under low power magnification, the image is darker.

• Under high power magnification, the image is lighter.