RNA
In order to better understand what
Ribonucleic Acid (RNA) is, it is first important to know
what is happening inside an organism’s cell.
Inside every living cell, the actual
process of creating new proteins undergoes several
different steps and the instructions for these steps are
contained in the nucleus of the cells. However, the
proteins themselves are synthesized outside the nucleus,
in an area known as the cytoplasm. This means
that the cells must have a way to relay the information
contained in the nucleus towards the cytoplasm. As it
turns out, cells utilize a special molecule known as the
messenger RNA to transcribe the genetic code found inside
the nucleus.
RNA is very similar to DNA,
Deoxyribonucleic acid, which contains the vital genetic
information of the cell. RNA, when compared to DNA, has
only a single strand and has a ribose sugar instead of
the deoxyribose sugar. Furthermore, the base of the RNA
is Uracil instead of Thymine which is found in DNA. RNA
is produced by the RNA polymerase enzyme. This enzyme is
responsible for RNA synthesis.
Whenever new proteins are needed by the
cell, it sends a chemical signal to the nucleus which
causes a gene for that protein to be 'switched on'. When
this happens, the DNA codes are copied to the messenger
RNA in the process known as genetic transcription. After
the codes have been copied, the messenger RNA carries the
information to the ribosome which is responsible for the
protein synthesis. The messenger RNA then releases the
codes to the transfer RNA which eventually translates the
codes in the right order inside the
ribosome.
Once the code is being translated in the
ribosome and the required protein is synthesized, a
mechanism known as RNA interference takes place,
turning off the gene so it doesn't send more
messenger RNA to the ribosome.
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