The Theme of Levels of Organization in Prokaryotes
While multicellular animals and plants like humans and sunflowers are clearly complicated, organized groups of cells, we often think of each bacterial cell as behaving independently. Sometimes, however, bacterial cells do work together to make organized structures.
Intraspecies Levels of Organization
We talked earlier about biofilms, which are communities of microbial cells, and how spores, which are dormant, protected bacteria. While some bacteria sporulate in planktonic form, others, notable myxobacteria, produce organized cell structures that help disseminate their spores. Consider the two images below.
Image from here.
The image to the left shows different bacterial structures called fruiting bodies. Fruiting bodies are kind of a bacterial version of a sunflower. The bacterial cells come together to develop into structures with spores on the top, ripe for spreading. The image to the right is a microscope image of several fruiting bodies produced by colonies of the mycobacterium Myxococcus xanthus.
Interspecies Levels of Organization
Many scientists study the populations of bacteria that develop on your teeth every morning. They are complex mixes of cells that land in a predetermined order every night. Some bacteria are really good at sticking to your teeth directly; the next species is good at sticking to those initial bacteria, and so on. This is organization on a mixed-species level.