Coulter counter

Definition

A Coulter counter is an instrument used to count and size cells by detecting changes in electrical resistance. It is commonly used to measure microbial populations.

5 Must Know Facts For Your Next Test

1. The Coulter counter works on the principle of electrical impedance.
2. It can provide both cell count and cell size distribution in a sample.
3. Samples must be in a liquid suspension for accurate measurement.
4. Coulter counters are highly effective for counting bacteria, yeast, and other microbes.
5. The data obtained from a Coulter counter can be used to analyze growth rates and population dynamics.

Review Questions

• What principle does the Coulter counter use to measure cell count and size?
• Why must samples be in liquid suspension for accurate measurement with a Coulter counter?
• How can the data obtained from a Coulter counter be utilized in studying microbial growth?

Related terms

Flow Cytometry: A technique used to detect and measure physical and chemical characteristics of cells or particles as they flow through a laser beam.

Spectrophotometry: A method used to measure the amount of light that a sample absorbs, often used for determining cell concentration.

Hemocytometer: A device originally designed for counting blood cells but also used for counting other types of cells under a microscope.