Bacterial reproduction, antibiotic resistance & evolution
Bacteria reproduce asexual, specifically via binary fission. Since bacteria reproduce asexually, this means that they are identical. However, there are some ways in which the genes of bacteria can change: transduction, conjugation, and transfer. Transdution is when new genes are introduced to the bacteria from viruses. Once the viral genes have entered the bacteria, it can combine itself with the bacteria genes. The bacteria will then undergo mitosis, reproducing the bacteria with altered genes (referencing the Lysogenetic cycle of viruses). Genes can also be changed through conjugation which is the direct transfer of genes (plasmids) from bacteria to bacteria from the pili. The last method of gene alteration is transformation, which is when the membrane of the bacteria is weakened enough that new genes can be taken up from its environment. An example of this is heat shock. In all the above examples, the DNA of the bacteria is changing, therefore we can state that evolution is occurring within the bacteria.
Additionally, bacterial infections are becoming harder to treat with antibiotics due to the excessive use of antibiotics. When a person contracts a bacterial infection, there are regular bacteria as well as some stronger ones. The person must take antibiotic over a set period to kill the bacterial. The antibiotics will kill the regular bacteria, however, if the antibiotics are not taken for long a long enough period of time, the stronger bacteria will live, then continue to reproduce. Now the population of bacteria is made up of mostly stronger bacteria, making is harder to kill them off with antibiotics. This situation can be a representation of natural selection, the fittest of the bacteria survive and reproduce. Now the infected person must take antibiotics for a longer period of time to eliminate all the bacteria in their body.
Additionally, bacterial infections are becoming harder to treat with antibiotics due to the excessive use of antibiotics. When a person contracts a bacterial infection, there are regular bacteria as well as some stronger ones. The person must take antibiotic over a set period to kill the bacterial. The antibiotics will kill the regular bacteria, however, if the antibiotics are not taken for long a long enough period of time, the stronger bacteria will live, then continue to reproduce. Now the population of bacteria is made up of mostly stronger bacteria, making is harder to kill them off with antibiotics. This situation can be a representation of natural selection, the fittest of the bacteria survive and reproduce. Now the infected person must take antibiotics for a longer period of time to eliminate all the bacteria in their body.