Final answer:
Bacteria have three common shapes: cocci (spheres), bacilli (rods), and spirilli (spirals), with examples including Staphylococcus aureus, Escherichia coli, and Spirillum minus respectively.
Step-by-step explanation:
Three Common Shapes of Bacteria
Bacteria are microscopic organisms that display various shapes which are key characteristics for their identification and classification. The three most common bacterial cell shapes include:
- Cocci (spheres) - An example of cocci is Staphylococcus aureus, known for causing staph infections.
- Bacilli (rods) - An example of bacilli is Escherichia coli (E. coli), found in the intestines of humans and animals.
- Spirilli (spirals) - An example of spirilli is Spirillum minus, a cause of rat-bite fever.
Each bacterial shape not only helps in classification but also may relate to the specific roles or environments where the bacteria are most successful.
The shape and, frequently, the arrangement of cells after binary fission can provide information about how a bacterium lives and reproduces.