Antibiotic resistance occurs when an antibiotic has lost its ability to effectively control or kill bacterial growth. The bacterium become resistant and continue to multiply rapidly. The antibiotics will target susceptible or weaker bacterial cells and will usually end up eliminating them, but for immune bacterial cells also known as Superbugs antibiotics are harmless. Some bacteria are naturally immune to antibiotics like penicillin, giving them a huge survival advantage. There are two other ways bacteria can become resistant to antibiotics. Since bacteria can replicate and reproduce so rapidly, when a mutation occurs many bacterium are able to develop the resistant trait. For example, when a mutation occurs the bacterial cell that is infected may develop the ability to produce potent chemicals (enzymes) that inactivate antibiotics, while other mutations eliminate the cell target that the antibiotic attacks. If no mutations occur however, certain bacteria may acquire antibiotic resistance from another bacterium that has the trait through the process of Conjugation. During this process the Plasmid (contains the resistant trait) will move through the philus tube and into the new cell. Thus giving that bacterial cell the new advantage. Bacterial cells can also can acquire this trait through Transduction which occurs when a virus injects its DNA into the bacteriophage. The resistant trait is packaged in the head of the virus and will then be injected into the bacterial cell, giving it the Superbug mentality. Our use of antibiotics is contributing to the development of Superbugs because the bacteria are becoming more and more immune to our methods of protection.
When a bacteria cell wants to alter or replicate its DNA it has four main options to reproduce itself or its offspring into the next generation. They are: Binary Fission, Conjugation, Transformation and Transduction. During the process of Transformation exogenous genetic material from the surroundings are directly taken in and incorporated through the cell membrane. In order for Transformation to work though, all bacterial cells must be in a certain physiological state. The state s referred to as competent. This process happens naturally in certain bacterial cells, as they are already competent. Transduction is the process by which DNA is transferred from one bacterium to another by a virus. In Transduction a virus may land on a bacterial cell. The virus will then pierce the cell wall with its tail and then insert its own DNA into the bacteriophage. Therefore alerting the genetic material within in that bacterium. The bacteriophage that was recently infected by the virus will then enter temperate cycles called the Lytic Cycle and Lysogenic Cycles.
The two ways a bacteria may reproduce come naturally through the processes of Binary Fission and Conjugation. Binary Fission, much like Mitosis occurs through asexual reproduction where there is one Parent Cell that replicates identical DNA and splits into two Daughter Cells. During this process the DNA or genetic material is not changing at all. The DNA and organelles of the cell move to opposite ends of the pole before splitting into two identical cells. On the other hand, Conjugation is the transfer of genetic material between two different bacterial cells. This occurs through direct cell to cell contact. Both are methods of reproduction within a single bacterium and they both end up producing a daughter cell(s). Some more similarities between Binary Fission and Conjugation are that they both contain a Plasmid and involve multiplying by cytoplasm or nuclear division. The difference between Binary Fission and Conjugation is the change in DNA. Binary Fission's DNA replicates and stays the same, while Conjugation focuses solely on the transfer of genetic information between bacterial cells. In order to replicate its DNA (Binary Fission), no mates are required whereas, Conjugation requires a mate making it a sexual reproduction apposed to asexual. Binary Fission produces identical daughter cells where Conjugation creates two genetically different daughter cells. In terms of rapid production, Binary Fission is able to make more bacteria cells in a shorter amount of time as things seem to happen quiet fast during this process. Conjugation does things the exact opposite, as it needs time to create the protein link called a pilus or conjugation tube; therefore taken more time and producing at a smaller rate. The existence of Superbugs is credited to conjugation, as this is how the Superbug gene is passed on to other bacterial cells.
When microscopic invading agents such as bacteria, fungi or viruses organize a plan to infect and invade our bodies, our immune system is alerted and put into defense mode. Luckily, for us our body has a couple layers of protection to keep us from getting sick. The first layer is our skin, which delays all pathogens from freely entering, as the membranes in our skin cells are semi-permeable only letting in certain things. When you suffer a cut, our blood clots to stop pathogens from getting through. Your throat and nose ventilation systems are lined with mucus that catches pathogens not to mention the acid that is located in your stomach. However, from time to time the sneaky and slimy pathogens will find a way through the first layer of protection. That is when our second layer of protection kicks in, White blood cells. They ingest pathogens, produce antibodies or produce antitoxins to counteract the toxins made by bacterium. The White Blood Cells in our system serve as our army, as it protects our bodies from foreign invaders by demolishing any harmful toxin that it can find in our system. The second way our bodies can defend against dangerous pathogens correlates to prescribed antibiotics and medicines from a pharmacists or doctor. These are man-made medicines, usually created from fungi. This method will destroy all foreign pathogens but may also wipe out important bacteria's needed for our body's everyday functions. The third and most effective way our bodies can help prevent or fight off sickness/diseases is by becoming immune. In order to become immune, our body will need to be injected by a vaccine which is a dead or weakened part of the microscopic invading agents. This stimulates the body's immune system and prepares it for battle. But this weakened virus, fungi or bacteria is not strong enough to take over the body or make it ill; so that the next time our bodies come in contact with this sickness it is able to recognize and fight it off before becoming too sick to fight back.
The Lytic Cycle and Lysogenic Cycle of a virus are the two ways it reproduces once it has infected a suitable host cell and taken over its control system. Although these are both ways in which a virus reproduces they have distinct differences between them. Lytic Cycle of a Cold Sore Step 1 consists of the cold sore virus locking its tail fibers into the host cell's receptors on the outside of the membrane, as it locks in. The tail of the virus will pierce the surface of the host cell and the viruses' DNA will then be injected into the host cell's system. Step 2 comes into play when the viruses DNA forms a circle next to the host cell's DNA. This step us very simple but plays a huge role down the road for further infection. Step 3 is all about the infection. During this stage the virus has now taken over the host cell's metabolism, as it is instructing the host cell to synthesize nucleic acids and proteins for the virus it is creating. New virus parts are now being created and developed faster and faster by the second. Step 4 calls for the assembly of newly created cold sore viruses. These viruses are now fully reproduced and ready to infect more host cells. Step 5 occurs when the host cell obtains too many cold sore viruses. The host cell's walls burst open due to the over abundance of viruses. The newly created cold sore viruses have now killed the host cell and wander through the inside of the body looking for another suitable host cell to infect. Lysogenic Cycle of a Cold Sore The first step of the Lysogenic Cycle and Lytic Cycle are identical. The cold sore virus locks its tail fibers into the host cell's receptors on the outside of the membrane. The tail of the virus will pierce the surface of the host cell and the viruses' DNA will then be injected into the host cell's system. Once the DNA has entered the host cell's system, the viral DNA will form a circle right beside the chromosomal DNA (host cell's DNA). Step 3 is where the Lytic and Lysogenic Cycle start to differ. Instead of taking over the host cell's metabolism and ordering the construction of viral proteins, nucleic acid and DNA; the prophage will fuse itself into the host cells DNA. From there it will wait or remain dormant and replicate for an extended period of time. This may last a couple days, a couple months or a couple generations. Eventually, something will trigger the viral DNA to take action. The viral DNA will disconnect from the host cell's DNA and will go through the Lytic Cycle. Scientist over many generations of extensive research have come up with the conclusion that viruses are not living organisms. Viruses lack the ability to metabolize, meaning they can not reproduce themselves. In order for a virus to live and reproduce it must find a suitable host cell. Once they have found its suitable host cell they may take it over and use metabolize on behalf of its host's already living material. A virus cannot live more than 48 hours away out of its host cell which is another reason why scientist believe viruses are not alive. "Viruses are not classified as being alive because they don’t have their own machinery for reproducing. They can only take over the machinery of cells, turning them into virus factories" said a scientist from UCSB Science Line. In conclusion viruses are thought of as non-living because they lack most of the criteria that scientist evaluate living things on.
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