- Thermophiles are found in mineral springs and thermal volcanic vents on the ocean floor. Halophiles are found in the waters of extreme salinity of 15%-20%. Some methanogens are important symbionts in termites and other herbivores. Some methanogens are important decomposers in marshes and swamps. Thermophiles have hot habitats that are 60-80 degrees Celsius. Acidophiles are found in acidic habitats with pH levels ranging from 2-4.
- Prokaryotes are very common on earth, and they have a population that is ten times larger than eukaryotes. Because they are the dominant species, they play a large role in the environment.
- Bacterial cell walls differ from plant cell walls because plant cell walls are made of cellulose or chitin and bacterial cell walls are made of peptidolycans, which make the walls rigid too.
- The cell wall aids in classifying bacteria through the gram staining method. Bacteria is classified into two groups which are gram positive and gram negative. Gram positives are bacterias with larger amounts of peptidoglycan, and this means that they have simpler and less complex cell walls. Gram negative bacterias have less peptidoglycan in their cell walls, and they are more complex with membranes that have lipopolysaccharides.
- Molecular systematics have classified prokaryotes into two domains because ribosomal RNA shows the evolutionary relationships of organisms. The ribosomal RNA displayed that some prokaryotes were closely related to eukaryotes, and they should have their own category. The special category for these prokaryotes is Archaebacteria, and the other prokaryotic category is Eubacteria.
- Bacteria play a role in recycling nutrients because they are decomposers. Decomposers are organisms that break down organic molecules and compounds for nutrients from dead matter, and then these broken down molecules can be used by other organisms for food. Thus, the nutrients are recycled instead of wasted.
- Five scientific and commercial purposes that humans exploit prokaryotes for are that pharmacy companies use cultured bacteria to make vitamins and antibiotics, simple models like E. Coli are used to understand molecular biology, the food industry uses it to convert milk into yogurt and cheese, methanogens are used to digest organic wastes at sewage plants, and some pseudomonads are used to decompose pesticides.