Health Essays

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