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Telomere

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<p><span style="font-size:18px"><strong>&nbsp;Abstract</strong></span></p>
<p>Telomere = Telo&nbsp;[Greek nouns telos (<em>&tau;έ&lambda;&omicron;&sigmaf;</em>) &#39;end&#39; ] + Mere [Greek (<em>&mu;έ&rho;&omicron;&sigmaf;</em>, root: <em>&mu;&epsilon;&rho;-</em>) &#39;part.&#39;], meaning ending part.</p>
<p>Telomere protects the end of the chromosome from degradation by being truncated itself instead of chromosome.</p>
<p>It is known that telomere length is getting shortened during thechromosome replication in cell division,</p> <p>as DNA polymerase cannot continue its duplicating work to the end part of chromosome.</p> <p>So&nbsp;when&nbsp;duplication of chromosome is done,&nbsp;the end of the chromosome is shortened.</p>
<p>Telomere consists of repetitive nucleotide sequences. For vertebrates, the sequence of telomere&nbsp;nucleotides is TTAGGG.</p>
 
<p>This TTAGGG sequence is approximately repeated 2,500 times in human telomere.</p>
 
<p>So&nbsp;the shortened part of chromosome means the&nbsp;repetitive part of telomere, by truncation occurred during cell division to protect genes on chromosomes.</p>
 
<p>During the lifetime, as individual gets through cell division, the telomere ends become shorter and shorter.</p>
 
<p>Then when all the telomeres are gone, cells stop the division,&nbsp;chromosomes remain only strands part, then die with aging.</p>
 
<p>Because of this, telomere is pointed as a determining individual&#39;s&nbsp;aging and lifespan.</p>
 
<p>However, telomeres can be also replenished by an enzyme called telomerase reverse transcriptase.</p>
 
<p>&nbsp;</p>
 
<p><span style="font-size:18px"><strong>Discovery History</strong></span></p>
 
<p>In the early 1970s : First recognization of telomere existence by notifying the shorter ends of chromosomes during replication. (Alexei Olovnikov)</p>
 
<p>In 1975&ndash;1977 : Discovering simple repeated DNA sequences&nbsp;located at end part of chromosomes.&nbsp;(Elizabeth Blackburn, Joseph Gall)</p>
 
<p>In 2009 : Discovering mechanism&nbsp;for protecting&nbsp;chromosomes&nbsp;by&nbsp;telomere and telomerase.&nbsp;(Blackburn, Carol Greider, and Jack Szostak)</p>
 
<p>&nbsp;This discovery was awarded the 2009 Nobel Prize in Physiology or Medicine.</p>
 
<p>&nbsp;</p>
 
<p><strong><span style="font-size:18px">Raised Questions about Telomere and Aging</span></strong></p>
 
<p>During the class, some questions involved in telomere and aging&nbsp;were suggested by classmates.</p>
 
<p>1. What is the&nbsp;exact&nbsp;definition of aging?</p>
 
<p>2. Between biological age and real-time age, which one&nbsp;can be said&nbsp;real age?</p>
 
<p>3.&nbsp;Can the truncation of telomere explain all the aging reason?</p>
 
<p>4. Is the telomere sequence same in chromosomes of different kind of cells?</p>
 
<p>And so on, so from now on, conclusions from my&nbsp;investigation and analysis&nbsp;would be covered in this page.</p>
 
<p>&nbsp;</p>
 
<p><span style="font-size:14px"><strong>1. What is the exact definition of aging?</strong></span></p>
 
<p>Aging means the process of becoming older. Usually age of&nbsp;individual&nbsp;can be counted from the time when it was born, and it is called&nbsp;chronological aging. Meanwhile, biological aging, as known as senescence, means the steady&nbsp;deterioration&nbsp;of&nbsp;cell characteristics&nbsp;that could function&nbsp;for continuing&nbsp;life activity.&nbsp;During the biological aging,&nbsp;cells&#39; ability to maintain viability&nbsp;declines while tendency to be vulnerable to mortality&nbsp;grows after maturation.&nbsp;In sum, there are two kinds of definitions for aging - Real-time aging counted from time processing, and Biological aging counted by accumulation of cell malfunction.</p>
 
<p>&nbsp;</p>
 
<p><span style="font-size:14px"><strong>2. Between biological age and&nbsp;chronological age, which one&nbsp;can be said&nbsp;real age?</strong></span></p>
 
<p>Usually there is a proportional relationship between real-time age and biological age, since&nbsp;cells tend to be damaged&nbsp;to be vulnerable to mortality as the time goes on. The more time the individual goes on, its&nbsp;cells &nbsp;(Processing)</p>
 
<p>&nbsp;</p>
 
<p><span style="font-size:14px"><strong>3.&nbsp;Can the truncation of telomere explain all the aging reason?</strong></span></p>
 
<p>(Processing)</p>
 
<p>&nbsp;</p>
 
<p><span style="font-size:14px"><strong>4.</strong></span><span style="font-size:14px"><strong> Is the telomere sequence same in chromosomes of different kind of cells?</strong></span></p>
 
<p>(Processing)</p>
 
<p>&nbsp;</p>
 
<p>&nbsp;</p>
 
<p>[The (Processing) phrase would remain until I complete my opinions after the question.]</p>
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