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1. A few examples of things that can affect our growth and change throughout our lifetime are: telomeres, mutations, DNA and epigenetics. DNA is short for deoxyribonucleic acid, the building block of life that provides the hereditary material that is a blueprint for living organisms. It determines our physical features which are passed on to us from our parents through 23 chromosomes. Genes determine height, hair color, eye color and many other traits. Genetic disorders occur because of a harmful mutation in a person’s DNA. Some examples of genetic disorders include Down syndrome and cystic fibrosis. Recently several studies have shown that various genes may be responsible for regulating aging, immunity and other factors related to longevity. Therefore, genes are also responsible for how long we live and the aging process. Telomeres can also affect longevity. A telomere is a region of repetitive DNA at the end of a chromosome, which protects the end of the chromosome from deterioration. During cell division, enzymes that duplicate the chromosome and its DNA cannot continue their duplication all the way to the end of the chromosome. Every time a cell divides the telomere becomes shorter. If cells divided without telomeres, they would lose the ends of their chromosomes, and the necessary information they contain. The telomere shortening mechanism normally limits cells to a fixed number of divisions, and animal studies suggest that this is responsible for aging on the cellular level and sets a limit on lifespans. Epigenetics plays a role in how our bodies change throughout our life. It is the study of changes in gene activity that do not involve alterations to the genetic code but still get passed down to at least one successive generation. The epigenome sits on top of the genome. Methyl groups made of carbon and hydrogen bind to genes and give instructions on what to express or not express. It is these epigenetic "marks" that tell your genes to switch on or off. It is through epigenetic marks that environmental factors like diet, stress and prenatal nutrition can make an imprint on genes that is passed from one generation to the next. The epigenome doesn’t change your DNA but decides how much genes are expressed or not expressed. The epigenome tells the genome what to do. The epigenome changes throughout our life due to environmental factors like diet, smoking or stress levels. These environmental factors can cause methyl groups to attach to the wrong places. This can cause cells to become abnormal and diseases can form. All of these factors can affect how and why we grow and change throughout our lifetime.
2. An antibody is a specialized protein, produced by white blood cells, which can recognize and neutralize specific microbes. An example of an antibody are the antibodies around blood cells. Every blood type has a different combination of antibodies. Blood type A has the antibody B around the blood cells and therefore doesn’t allow blood type B near it. Blood type B has the antibody A around it. Blood type AB has neither antibody A or B around it and therefore is the universal recipient of blood because it doesn’t reject any other blood types. Blood type O has both antibodies A and B around the blood cells and therefore is the universal donor. The antibody will grab onto the antigen and won’t allow it to enter the cell. Antibodies have complementary surface markers that work with the antigens like a lock and key model. When an antigen appears in the body, it encounters an antibody with a complementary pattern. The antibody then locks onto the antigen and triggers a series of events designed to destroy the invading pathogen. The body does not however synthesize the appropriate antibody lock after it comes in contact with the antigen key. The antibodies already exist for millions of possible antigens. By destroying the pathogen, the antibodies help destroy or cure the disease. An antigen is a marker on the surface of a foreign substance that immune system cells recognize as non-self and that triggers the immune response. An example of an antigen are the antigens on blood cells. Every blood type has a different combination of antigens. Blood type A has the protein Antigen A on it. Blood type B has the Antigen B on it. Blood type AB has both Antigen A and Antigen B on it. Blood type O has neither Antigen A or B located on the blood cells. All cells within the body display markers on their surfaces which are tiny molecular shapes that identify them as “self” to lymphocytes that encounter them. Invading microorganisms also display markers on their surfaces. Lymphocytes can identify these as foreign or “non-self”. These non-self markers that trigger the immune response are known as antigens. Therefore the antigens cause an immune response to occur because this is how the body recognizes pathogens that enter the body. Once the lymphocytes recognize the antigen the antibodies take over by destroying them. Antigens help destroy or cure disease because they trigger the immune response which destroys any harmful pathogens in the body. An antigen is any substance that causes your immune system to produce antibodies against it. An antigen may be a foreign substance from the environment such as chemicals, bacteria, viruses, or pollen. An antigen may also be formed within the body. An antibiotic is a medicine that inhibits the growth of or destroys microorganisms. Some examples of antibiotics are: penicillin, amoxicillin, ampicillin, cephalosporin and streptomycin. Antibiotics are powerful medicines that fight bacterial infections. Used properly, antibiotics can save lives. They either kill bacteria or keep them from reproducing. It will kill the desired bacteria, but not the cells in your body. Each different type of antibiotic affects different bacteria in different ways. Although there are a number of different types of antibiotics they all work in one of two ways. One way is if the antibiotic is a bactericidal antibiotic which kills the bacteria. Penicillin is a bactericidal. A bactericidal usually either interferes with the formation of the bacterium's cell wall or its cell contents. Another way is if the antibiotic is a bacteriostatic which stops bacteria from multiplying. By killing the bacteria, the antibiotic helps prevent the infection from getting worse and helps to cure disease caused by bacteria.
3. The epigenome means "above" the genome. The epigenome consists of chemical compounds that modify, or mark, the genome in a way that tells it what to do, where to do it and when to do it. The marks, which are not part of the DNA itself, can be passed on from cell to cell as cells divide, and from one generation to the next. The protein-coding parts of the genome, called genes, do not make proteins all of the time in all of the cells. Instead, different sets of genes are turned on or off in various kinds of cells at different points in time. Differences in the types and amounts of proteins produced determine how cells look, grow and act. The epigenome influences which genes are active, and which proteins are produced, in a particular cell. The first type of mark is DNA methylation which directly affects the DNA in your genome. In this process, ch...