The process by which a doublestranded DNA molecule is copied
to produce two identical DNA
molecules.
Deoxyribonucleic acid is copied during interphase prior mitosis and meiosis.
 It is important that new copies are exactly like the original molecule.
 The structure of the DNA provides a mechanism for making accurate
copies of the molecule.
 The process of making copies of DNA is called replication. When DNA replicates,
two identical copies of DNA molecules are produced , which are exactly the same
as the original.
it is a theory starting that
genetics information flows
only in one direction, from
DNA to RNA, to protein, or
RNA directly to protein.
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DNA
RNA
Ribonucleic acid (abbreviated RNA) is a
nucleic acid present in all living cells that
has structural similarities to DNA
protein
(PROH-teen)
A molecule made up of amino acids.
Proteins are needed for the body to function
properly.
Step 1. An enzyme called helicase breaks the bond between nitrogenous bases. The two
strands of DNA split.
Step 2. The bases attached to each strand then pair up with the free nucleotides found
in the cytoplasm.
Step 3. the complementary nucleotides are added to each strand by DNA
polymerases to form new strands.
• DNA is made up of sugars, phosphate groups,
and nitrogenous bases and its shape is a
double helix. The complementary structure the
two strands of DNA allow each strand to serve
as a template during replication.
• The specificity of base pairing in DNA, adenine
with thymine, and cytosine with guanine, allows
DNA to replicate itself with accuracy.
Protein production is similar to
car production. It is the role of
the DNA to provide workers
with the instructions for making
the proteins, and the workers
build the proteins.
Three types of RNA
• One type of RNA, messenger RNA (mRNA) brings
information from the DNA in the nucleus to the
protein manufacturing area, the cytoplasm. In the
cytoplasm, the mRNA becomes the template of
information to make protein
• Ribosomes, made of ribosomal RNA (rRNA), and
ribosomal proteins hold tightly into the mRNA
using its information to assemble the amino acids
in correct order.
• Transfer RNA (tRNA) supplies amino acids to the
ribosome to be assembled as protein.