SCYM Principles of Flow Cytometry & Instrumentation 3

Question 1

What is spectral spillover in multicolor flow cytometry?

Accepted Answer

Fluorescence emission from one dye detected in a channel designated for another dye

Answer

Spectral spillover occurs because fluorochromes emit across a broad spectrum, causing a portion of one dye's emission to be detected in channels designed for other dyes.

Question 2

Which control is used to set the compensation matrix in multicolor flow cytometry?

Accepted Answer

Single-stain compensation control

Answer

Single-stain compensation controls, containing only one fluorochrome at a time, are used to measure and mathematically subtract spillover from each fluorochrome into other channels.

Question 3

What does the side scatter (SSC) parameter primarily reflect in flow cytometry?

Accepted Answer

Internal complexity, granularity, and nuclear structure

Answer

SSC is generated by light scattered at approximately 90° from the laser beam, reflecting internal complexity such as granularity, nuclear lobularity, and intracellular structures.

Question 4

In electrostatic cell sorting, what determines which droplets receive an electrical charge?

Accepted Answer

Whether the cell in the droplet meets the sort gate criteria

Answer

The sorter's electronics evaluate whether the cell meets the pre-defined sort gate criteria and, if so, apply an electrical charge to the droplet at the moment it breaks from the stream.

Question 5

What is the typical laser power range used in most clinical and research flow cytometers?

Accepted Answer

5–100 milliwatts

Answer

Most flow cytometers use lasers in the 5–100 mW range, which provides sufficient power to excite fluorochromes without causing excessive photobleaching or cell damage.

(SCYM) Specialist in Cytometry Practice Test

(SCYM) Specialist in Cytometry Practice Test

SCYM Principles of Flow Cytometry & Instrumentation 3