A2.2.2 - Microscopy Skills

What are temporary mounts used for?

to quickly observe dynamic processes of living or fresh specimens (like cell movement or division) without complex preparation

What do stains do?

enhance the visibility of cellular structures by adding contrast

What are the two different kinds of stains and their differences?

• methylene blue: stains nuclei

• iodine: stains starch granules

What are the three steps to focus a light microscope?

1. position slide

2. course focus - location

3. fine focus - clarity

What is an Eyepiece Graticule?

a scale etched onto the eyepiece lens that allows measurements in eyepiece units (EPU)

calibration

the process of determining the actual length represented by one EPU at a specific magnification

what is a micrometer?

a slide with a known scale

Why is calibration necessary when using EPUs?

because the size of one EPU varies with magnification, and calibration determines the actual length represented by one EPU

What are the three essential guidelines for biological drawings?

1. clean, continuous lines (no shading)

2. label structures with straight lines

3. include mag. or scale bar

why are quantitative observations important?

they provide precise data that can be compared and analyzed