Bacteria

1. Bacteria

2. Prokaryotes • All bacteria are Prokaryotes • They classify as Archaebacteria and Eubacteria • Prokaryotes lack membrane bound organelles. • Lack a nucleus

3. Shapes Of Bacteria • There are three possible shapes for Bacteria • Bacilli which are rod shaped bacteria. • Cocci- are spherical shaped bacteria. • Last spirilla are spiral shaped bacteria.

4. Eubacteria • Is one the of two kingdoms of Bacteria. • These bacteria can be found all over the planet. • They are the most common bacteria. • Many of these bacteria are photosynthetic.

5. Archaebacteria • Archaebacteria are extremely uncommon. • They tend to live in extreme environments such as thermal vents in the bottom of the sea. • They resemble the first known prokaryotes.

6. Genome • One double standed, circular DNA molecule • Nucleoid = region of condensed DNA • 4.6 million nucleotide pairs = 4,400 genes • 100x more DNA than a virus • 0ne thousandth the DNA in a human

7. DNA replication • One (single) origin of replication • DNA synthesis in Both directions

8. Bacterial Reproduction • Binary Fission: reproduction for bacteria. • The bacterial cell will grow to roughly double its normal size and then begin to cleave. The cell splits into two replica daughter cells.

9. Conjugation: exchange genetic material • Plasmid: Small, circular bit of DNA that carry a few genes. In addition to the bacteria’s singular, circular chromosome (genome) • F plasmid: allows bacteria to do cojugation: exchange gentic material with another. • R plasmid: gives bacteria, resistance to antibiotics.

10. Bacterial transformation • Bacterial transformation: involves the direct uptake of foreign DNA, conferring a particular trait to the recipient • Plasmid can be picked up by nearby bacteria • Transduction: requires a virus as a vector, to help the bacteria pick up a piece of foreign DNA

11. Mutation: Genetic variation • Bacterial Reproduction: Asexual: Binary Fission: rapid • E.Coli in lab can reproduce every 20 minutes • Make a colony of 108 In 12 hours • Slower in nature: 12 hours to dbl amount of E.Coli in colon

12. How Bacteria cause disease • Bacteria cause disease by reproducing. In general the bacterial releases a toxic waste that kills or interferes with bodily functions. • In other cases though the bacteria will intentionally attack the cells around it.

13. An example of Disease • An example of a bacterial infection is when the streptococcus bacteria begin reproducing in the body. They release toxins into the body that attack, or harm the tissues of the throat. Which results in swelling of the throat and cell death. This is the cause of strep throat.

14. How to fight Bacteria • Antibiotics are the best way to fight off a bacterial infection. The antibiotics create an environment that is hostile to the bacteria. This allows the body to finish off the rest of the bacteria and finish off the infection. • Most importantly Antibiotics do not kill all bacteria. • Which is why overuse of antibiotics such as hand sanitizer become ineffective from overuse, because the remaining bacteria reproduce creating bacteria that are resistant/immune to the antibiotics. • These would be known as “super bacteria” because of the Natural selection process.

15. How bacteria play a role in the ecosystem • The large majority of bacteria on the planet are actually helpful. • In the nitrogen cycle which is one of the cycles necessary for all life, the bacteria in the soil recycle the dead organisms and their left over material. These nitrogen fixing bacteria provide fixed nitrogen for plants who then use it to create proteins ect. This process repeats. • Last in the digestive tracks of animals such as humans bacteria help us to digest our food.