Question

Contrast in differential interference contrast (DIC) microscopy depends on____________.

A) the amount of stain taken up by the cells
B) the amount of light used to illuminate the specimen
C) the rate of change of refractive index across the specimen
D) the rate of change of lipid content across the specimen
E) the amount of radiolabel applied to the specimen

Answer 1

Contrast in DIC microscopy is based on the rate of change of refractive index across the specimen, which results in an interference pattern that enhances image contrast.

Step-by-step explanation:

Contrast in differential interference contrast (DIC) microscopy depends on the rate of change of refractive index across the specimen. In DIC microscopy, a polarized light source is separated into two beams that are polarized at right angles to each other.

As these beams pass through the specimen, they experience different optical paths because of the varying refractive indices of the specimen's components. When the beams are recombined, they interfere with each other, and this interference pattern yields an image with enhanced contrast and shadowing, highlighting structures within the specimen that would otherwise be difficult to discern.