|Why is it important for DNA to be duplicated
|Question Date: 2019-02-14|
As you probably know, mitosis is what
happens in cell division before the one cell
finishes dividing into two new cells. The
DNA is basically a recipe book. It contains
directions for making all the proteins that
make us work. Proteins include most of the
structures that give us shape and strength, the
enzymes that control our countless chemical
reactions. Some of our hormones, antibodies that
fight disease, and lots more.
Each cell has the complete set of instructions,
but if it’s going to divide, each of the new cells
needs its own set. Imagine that you are part of a
team that is following directions to do something
like put together a bunch of chairs. Let’s say
your team decides to split up and work in two
smaller teams. Each team will need its own set of
directions. You would probably take a picture or
take them to a photocopier. In a cell, the DNA
is copied when a bunch of enzymes helps to
synthesize (make) new DNA strands.
Sometimes a mistake is made in copying the DNA.
This is called a mutation. The mutation may
be good, bad, or neither one. These mutations
are the raw material for natural selection because
they create genetic variation in a population.
What kinds of cells do you think divide a lot?
Which ones don’t divide at all?
Thanks for asking,
During mitosis, the cell creates a second copy
of itself. Prior to duplicating its DNA, the
cell also duplicates all of its organelles. In its
normal state, a human cell has 23 pairs of
chromosomes. During mitosis, that number becomes
46 homologous pairs. This is so that each cell
ends up with 23 pairs of chromosomes following
cell division. If the cell did not duplicate
its DNA (something that happens during meiosis
to produce gametes), then each daughter cell
would only receive one copy of each chromosome.
Instead of having 23 pairs, the cells would each
have 23 chromosomes (in other words, each cell
would be haploid).
is the process by which somatic
(non-reproductive) cells divides. It
produces two daughter cells which are identical to
each other and to the original cell. These new
cells replace old and damaged cells with new ones.
The vast majority of cells in any organism are
somatic cells, and many have specialized
functions like those making up heart muscles
and neurons. Because the daughter cells are
supposed to fulfill the same special function as
the parent, they need to be programmed the same
way so they can grow and mature properly.
this programming in the sequence of the
bases which make up each chain. Thus, to ensure
that the daughters can fulfill their role, the
parent cell makes sure each receives a full set of
While it is conceivable that each
daughter cell could receive a single strand of DNA
from the parent and then produce the complementary
strand, there are a
number of reasons this would not be
favorable. These range from potentially
compromising the genetic sequence (the
double strand of DNA is more stable than a
single strand and also allows checking of the
code ) to being an inefficient use of energy.
If the DNA weren't duplicated, then there wouldn't
be enough to give to each daughter cell, which
would mean that the cells produced wouldn't have
enough DNA to survive.
DNA replication during mitosis is extremely
important. Since one cell is turning into two,
it’s important that they each get their own
sets of DNA after they split. Imagine you are
a cell and you’re holding the book of DNA. That
book contains the building blocks of everything
you need to be a cell; it tells you exactly what
to do all day and when. If you underwent mitosis
to create another duplicate cell, you would want
that cell to also have the book of DNA. Therefore,
you’d have to make copies of all the pages you
have and give them to the new cell before he
departs, otherwise the new cell wouldn’t know how
Every cell needs to have the proper amount of DNA,
so when 1 cell divides into 2 cells during
mitosis, it needs to have 2 copies of all the DNA.
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