Microbiology
Microbiology
Welcome to Unit 2, Microbiology
This unit we covered Viruses and Bacteria, learning such things as retroviruses, gram staining, antibiotic resistance and much more!
Are Viruses Alive?
Viruses, tiny particles which are infectious and are too small to be seen by the naked eye, which resemble life but does not fit all the characteristics of living things. Though virus may fit a few, there are many characteristics which describe them as non-living. In order to be classified as a living thing, a specimen must fit the 8 characteristics of living things. Those are;
All living things must apply to everything. Viruses do not apply to everything. They do not reproduce independently, and must use a host cell in order to produce more viruses. The host combines their and the viral DNA to combine either prophage or provirus, produces viral protein, and assembles new viruses. They cannot metabolize, which is the chemistry of life and produces energy for. Without the process of metabolism, a virus cannot be considered a organism. The structure of a virus does not include cytoplasm, a jelly like substances which fills the interior of the cell and contains cell structures. It also does not contain regular organelles. When living things are deprived of water, they will die, while viruses can be crystallized and still be infectious. Viruses also can contain either DNA or RNA, while organisms only contain DNA. Having RNA helps the viruses be quicker in infecting because it takes out the process of turning DNA into RNA, which means it can immediately produce proteins. Lastly, viruses cause contagious diseases that attack immune systems.
In conclusion, those many reasons are why viruses are not considered a living organism.
In conclusion, those many reasons are why viruses are not considered a living organism.
Herpes and the Lytic and Lysogenic Cycle
The lytic and lysogenic cycles are processes in which a virus infect an organism. The two processes may result differently but are integrated and show how viruses can either case symptoms or be dormant.
The herpes simplex virus is virus which is transferred from bodily fluids. The virus is categorized into two types: Herpes Type 1 (HSV-1) or oral herpes, and Herpes Type 2 (HSV-2) or genital herpes. It is a retrovirus, meaning highly variable and has presently has no cure due to its high rate of mutation. A retrovirus is a type of virus which mutates much more rapidly than enveloped viruses and contain RNA. The RNA allows the virus to create proteins quicker than viruses with DNA, since it takes out the step of transforming DA into RNA. Herpes can be found in both the lytic and lysogenic cycle
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Ways Our Body Defend Against Pathogens
Our human immune system is a marvellous complex machine which helps us fight off pathogens. Without it, a single virus or bacteria can easily eliminate us. There are many methods in which our body protects us, three of those ways are Phagocytosis, interferon and antibodies. Phagocytosis, which means cell eating, is the White blood cells immediate attack against pathogens. The White Blood Cells attack the pathogens by engulfing the pathogen. Once engulfed, they release enzymes from their lysosomes. The remains are rejected and used by antibodies.
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Antibodies are highly specific proteins made by the White blood cells. They attach to the viruses and clumps them together, which deactivates them, and makes them easy to destroy by the WBC.
Interferon is also another way the immune systems defends itself from intruders. When a host cell is being destroyed by lysis, it can create a protein which acts like a signal. That protein warns other cells of the outbreak and activates the immune system. Without the protein, the infection can spread without warning.
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Comparing Binary Fission and Conjugation
Reproduction of bacteria is a process which can include two different procedures, Binary Fission and conjugation. Binary fission and conjugation are both vastly different and similar at the same time. They are both methods of reproduction which result in a new cell. They also both include the coping of DNA and possibly plasmids for a different cells purpose. And lastly they both end up going through the process of binary fission. Though in a general aspects they are both modes of reproduction Conjugation and Binary fission do have many separate characteristics. Conjugation is a method of transferring genes directly through other bacteria (Sex). It involved contact and two or more specimens, unlike binary fission. In this process you result a genetically variable “offspring” which a mixture of features, While in binary fission the product is two identical daughter cells which have the exact DNA composure as the parents cell. In conjugation, genes from a plasmid are given from a donor cell to a recipient cell, and the DNA is integrated and circulizes to become the recipient’s plasmid. Two other structural differences is that conjugation involves the use of a gene called the “F Factor’, which allows a bacterium to become the donor cell, and a “sex pilus” or “ Conjugation tube” is required to transport the DNA to the recipient. And In Binary fission, a bacterium produce asexually (one parents) and only needs the single bacterium. It does not involve any contact. It is the most common form of bacterial reproduction.
Personal Diagram
Transduction And Transformation
Bacteria, prokaryotic cells, are microscopic and produce asexually (one parents) through Binary fission. The only downside to binary fission is the lack of genetic diversity that is why there is three different ways a bacterium can change its DNA. One process we have already touched upon and that is Conjugation, but there is two other methods that can add genetic variety to bacteria; Transduction and Transformation
Transduction: Transduction is the method of adding genetic diversity to a bacteria through a direct transfer of viral DNA from a virus to a bacteria. As we learned previously, viruses need a host cell to reproduce. A bacteriophage attaches to a host cell and empties out its capsid. The RNA or DNA circulizes and integrates into the bacterial DNA. Once the phages viral RNA/DNA is combined with the Bacterium’s DNA, it is refereed as a Prophage. The prophage is a mixture of both viral genetic material and bacterial DNA, therefore creating a new combination of genes and causes the bacteria to a genetic variety. The new variations can then be multiplied through binary fission and shared among other bacteria. Though a virus can kill off a host cell through lysis and steal most of its plasma membrane as camouflage, it still has a chance to survive and prosper with its new DNA sequence. Transformation Transformation is a process in which a bacterium steals leftover DNA from deceased bacteria. Bacteria can take this deceased DNA and add it to their own, therefore mixing their DNA into a new variation. Bacteria can enter a mode where the go out into their environment and scavenge leftover bits of genetic material, and once this frenzy is complete, they reproduce asexually through the means of binary fission. |
Antibiotic Resistance
Antibiotic Resistance is a way bacteria evolve and adapt to outsmart modern medicine. It is a frightening evolution which has made many medical finding invalid, and is a powerful battle that may prove all r medical progression useless. Over the course of almost a century a “miracle drug” has progressed us so rapidly and saved hundreds of lives. That very medicine is what we call antibiotics. These antibiotics fight against bacterial infections and had seemed like we had eradicated infectious pathogens and won the battle of harmful bacteria. But as us as a society progressed medically, so did bacteria. It is a known fact bacteria reproduce abundantly and rapidly, a lot faster than us humans. Trillions of new bacteria can form in merely 24 hours. So the evolution rate is much immediate then ours. We had introduced these antibiotics to the bacterial population, and spiked the mutation frequency. Since they multiply so quickly, more mutations are present, and with the mechanism of natural selection, the beneficial mutated bacteria have a higher rate of survival. Since antibiotics have been introduced, bacteria were given a new environmental threat. The beneficially mutated bacteria present who were resistant to the newly introduction antibiotics had surprisingly survived, and therefore had gone on to share their genetic DNA through transduction, conjugation, transformation and final reproduced through binary fission. Now trillions of bacteria had the resistant gene. This gene had decreased progress as bacteria who were not affected by antibiotics were still rampaging their infectious diseases. Since the creation of antibiotics, it’s been a race against modern medicine and bacterial evolution. Many lifesaving drugs had been eradicated because of a resistant mutated gene that had spread. And our use of antibiotics has not helped our side. Repetitively Introducing antibiotics gives the bacteria a greater need to mutate and resist, and when they are battling antibiotic, only the resistance bacteria is left to populate. When a whole population contains a resistance gene, it proves the antibiotic incapable. Patient’s lack of this knowledge leads them to demand their doctors to over prescribe antibiotics, growing the resistance. Also, not finishing n entre trail of antibiotics is dangerous in the sense that your body does not completely erase all the harmful bacteria. When you stop your prescription halfway, you leave the more resistant to thrive without the competitions of antibiotics. All those pesky bacteria are now free to reproduce and spread throughout our population. Though many fear such ends as a religious apocalypse, global warming or dramatic natural disasters, our number one threat to or world is the advancement of antibiotic resistant superbugs.