Answer:
Telomerase
Explanation:
Repetitive regions at the ends of Chromosomes are known as telomeres and these are crucial for chromosomal stability. There is no gene present and they provide protection to internal parts of chromosome. The telomeres are eaten up slowly by ‘DNA REPAIR MECHANISM’ after many division cycles, which is considered as ageing. That why, a cell can divide only certain number of times.
Some cells have ability to express an enzyme telomerase that maintain the length of telomere. The telomerase enzyme contributes to cell immortality by rebuilding the damaged telomere. Thus telomerase enzyme is necessary for cancer initiation and survival of tumor. Telomerase enzyme can make its own DNA by using its RNA as template
. It extends the overhang strands of DNA by using a comlementary DNA.
Proteins help in the development of muscle, acts in the immune
system and also as enzymes. They are considered as a <span>class of nitrogenous
organic compounds that are comprise of large molecules which contains one or
more long chains of amino acids and are a vital portion of all active
organisms.</span>
Mitosis is the phase of the cycle when the cell division occurs. :)
The ciliates<span> have both a </span>micronucleus<span> and </span>macronucleus<span>, which appear quite homogeneous in composition. The organelles of protozoa have functions similar to the organs of higher animals. The </span>plasma membrane<span> enclosing the </span>cytoplasm<span> also covers the projecting locomotory structures such as </span>pseudopodia<span>, </span>cilia<span>, and </span>flagella<span>.
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