Question

What level of light intensity should we use when performing hemocytometer counts, and how can this be achieved?

A) High light intensity; Achieved by using natural sunlight.

B) Low light intensity; Achieved by using a strong artificial light source.

C) Moderate light intensity; Achieved by using a hemocytometer with built-in lighting.

D) Variable light intensity; Achieved by adjusting the microscope's condenser and diaphragm.

Answer 1

The correct light intensity for hemocytometer counts is variable and is achieved by adjusting the microscope's condenser and diaphragm, as opposed to using a single static light intensity level. This allows for optimal viewing conditions and prevents specimen degradation due to inappropriate lighting.

Step-by-step explanation:

When performing hemocytometer counts, the level of light intensity should be moderate to avoid both underexposure and overexposure that may lead to degradation of the specimen or difficulty in viewing. The best option is D) Variable light intensity; Achieved by adjusting the microscope's condenser and diaphragm. This means that you can optimize the light conditions for the specific requirements of your sample. It's crucial to have control over the light intensity considering that as the magnification increases, the image becomes darker due to a decrease in light per unit area of the image. Adjusting the condenser, utilizing the iris diaphragm, and the rheostat (dimmer switch) are all methods that can be used to achieve the desired light level.