BIOLOGICAL EFFECTS OF RADIATION
Chromosomes, Genes, and DNA
Like the whole beach we mentioned that is composed of tiny grains
of sand and smaller particles, our bodies are composed of tiny cells.
These cells, which have different functions and different shapes, all
have nuclei, or centers.
Within these centers are string-like materials
called chromosomes, which are in turn made up of genes.
The genes are
also composed of a number of chemicals, the most important of which is
DNA, short for desoxyribonucleic acid.
All of these things are composed
of molecules and, their smaller parts, atoms.
These chromosomes, which
are a series of long and short worm-like or thread-like shapes, determine
the workings and divisions of the cell.
The genes, which are like
different bands of color or segments on a thread,
in making up the form of the chromosome.
form the genes.
each serve a function
The DNA and other chemicals
These chemicals contain codes, or chemical signals
which regulate the shape, form, and life of the genes.
The genes then
determine the shape and form of the chromosome, and the chromosome the
shape and function of the cell.
The cells ultimately control the shape
and form of our bodies.
Almost all the cells in our body are continuously producing new cells,
some slower, some faster.
It is easier to understand if we consider
that when we cut our hair, or fingernails, they grow again.
If we get
a cut or burn, the blood lost will be replaced, or the skin damaged
will be replaced.
This is done by the cells reproducing, or duplicating
themselves, and it is the basic process which allows us to grow to
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