A Level Biology Practice Exam

What is a stage graticule used for in microscopy?

1. To enhance contrast

2. To measure the size of a sample

3. To stain samples

4. To identify specific components

The correct answer is: To measure the size of a sample

A stage graticule is an important tool used in microscopy to measure the size of a sample. It is a micrometer scale that is placed in the eyepiece or on the stage of a microscope, allowing for accurate measurements of the specimens being observed. As you look through the microscope, the graticule overlays the image, enabling the user to determine the dimensions of structures or organisms at a specific magnification. This measuring capability is crucial in biological studies where quantifying cell sizes, lengths of organisms, or dimensions of various structures can provide significant insights into their functions and relationships. By using the stage graticule in conjunction with known scale values, researchers can derive accurate measurements, facilitating a deeper understanding of biological phenomena.