Microorganism

Rare card · No. 67236

A microorganism, or microbe, is an organism of microscopic size, which may exist in its single-celled form or as a colony of cells. The possible existence of unseen microbial life was suspected from antiquity, with an early attestation in Jain literature authored in 6th-century BC India. The scientific study of microorganisms began with their observation under the microscope in the 1670s by Anton van Leeuwenhoek. In the 1850s, Louis Pasteur found that microorganisms caused food spoilage, debunking the theory of spontaneous generation. In the 1880s, Robert Koch discovered that microorganisms caused the diseases tuberculosis, cholera, diphtheria, and anthrax. There are 5 main groups of microorganisms. Here are the different groups and their definitions: Bacteria: Single-celled prokaryotic organisms that lack a membrane-bound nucleus. They feature cell walls made of peptidoglycan and come in shapes like spheres (cocci), rods (bacilli), and spirals (spirilla). Archaea: Single-celled prokaryotes...

Read on Wikipedia · Image Photo by Eric Erbe, digital colorization by Christopher Pooley, both of USDA, ARS, EMU., Public domain