Genes

DNA is what makes up genes, and genes are
what make up chromosomes, and chromosomes are
what controls are cells, and cells are what control
our body. So, one could say that DNA controls our
body, it defines who we are, our looks, our
personality. Everything from our favorite colour to
our most disliked book, DNA is behind it all. But
how does it accomplish this task?

DNA is located in the nucleus, and on the
outside of the nuclear membrane are miniscule pores
for things to pass in and out of the nucleus. A gene
is much too big to to fit through one of these tiny
pores so it gets another chemical to do the job for it.
But why would a gene want to get out of the nucleus
in the first place? Well, outside the nuceus in the
gelly like cytoplasm of the cell is an organelle called
the ribosome. This organelle is where a chemical
essential for human life known as a protein is
constructed. Proteins are what we are made of,
everything from our cells to our hair are made of
proteins in some form or another. But, in order to
send its information to the ribosome, a gene can get
a chemical called mRNA (messenger RNA) to do it
for it. This chemical is very thin so it can carry only
limited amounts of information, only enough to
create one protein. To achieve the passing of
information, the mRNA enters the nucleus of a cell
and approaches the gene. The gene then sends a
portion of its information to the mRNA (this process
will be explained in further detail under DNA) and
the mRNA leaves the nucleus. The mRNA then
heads out of the nucleus and into the ribosome,
through pores very similar to those of the nuclear
membrane. It then gives the instructions to tiny
messengers known as tRNA (transfer RNA) to bring
in the specified types of amino acids (Amino acids
are what make up proteins). The tRNA brings in the
different types of amino acids and forms then into a
chain, creating a protein. Since there are only about
20 different types of amino acids, the order in which
the amino acids line up is critical. If, per chance, the
cell had been exposed to radiation, the gene's
information could have been distorted, hence making
distorted proteins, this could lead to serious diseases
like lukemia and cancer. After the process of
creating the protein is done, the protein will move
out to it's specified location. For example, if a cell
creates a skin protein, it will go directly to the skin
etc. The cell will repeat this process many times in
its lifetime to create sufficient proteins for a body to
survive. The gene may also be manipulated, an
example would be manipulating a pea plant gene to
create more peas, this process is known as
biotechnology and is described in more detail in the
section entitled genetic engineering.