Microbiology: Size and Scale of Microbes

These flashcards cover the vocabulary and key concepts related to the size and scale of microorganisms as discussed in the microbiology lecture.

Micrometer (µm)

A unit of length equal to one millionth of a meter (0.000001 m) commonly used to measure microorganisms.

Nanometer (nm)

A unit of length equal to one billionth of a meter (0.000000001 m), often used to measure viruses.

Human Cell Size

Human blood cells typically range from 10µm to 100µm in size.

Bacterium Size

Most bacteria range from 0.1µm to 5.0µm in size.

Virus Size

Most viruses are less than 1µm and usually between 40-200 nanometers in size.

Relative Size

The comparative size of particles, such as human hair (50-180µm), red blood cells (7-8µm), and viruses (from 20nm to 900nm).

Respiratory Droplets

Droplets that can carry particles and have a size range of 5-10µm.

Ebola Virus Size

Ebola virus can range from 500 to 1000 nanometers in size.

COVID-19 Virus Size

COVID-19 virus is approximately 0.1 to 0.5µm in size.

Dust Particle Size

Dust particles can be classified as PM10 (<10µm) and PM2.5 (2.5µm).

Visibility Limit

The minimum size particles that can be seen with the naked eye is around 10-40µm.

Bacteriophage Size

Bacteriophages range in size from approximately 20nm to 900nm.

Viral Structure

Many viruses such as HIV, influenza, and herpesviruses have specific nm sizes, indicating their small scale.