The Structure of the
DNA Molecule
The finger print that is inside your
body!
DNA stands for:
D: Deoxyribose
N: Nucleic
A: Acid
DNA is too small
to see, but under a
microscope it looks
like a twisted up
ladder!
Every living
thing has DNA.
That means that
you have something
in common with a
zebra, a tree, a
mushroom and a
beetle!!!!
DNA is made up of steps and rails of a ladder.
This is a rail
This is a step
Green can only go with Red
Purple can only go with Yellow
Deciphering DNA's structure.
1. DNA is made up of subunits which
scientists call nucleotides.
2. Each nucleotide is made up of a sugar, a
phosphate and a base.
3. There are 4 different bases in a DNA
molecule:
a.
b.
c.
d.
adenine (a purine)
cytosine (a pyrimidine)
guanine (a purine)
thymine (a pyrimidine)
Nucleotides
1. DNA is made up of subunits which
scientists called nucleotides.
A nucleotide is a chemical
compound that consists of 3
portions: a nitrogenous
base, a sugar, and one or
more phosphate groups.
2. Each nucleotide is made up of a sugar,
a phosphate and a base.
3. There are 4 different bases in a DNA
molecule:
a. adenine (a purine)
b. cytosine (a pyrimidine)
c. guanine (a purine)
d. thymine (a pyrimidine)
Nucleotide Base Pairing
• Adenine always pairs with Thymine
• Guanine always pairs with Cytosine
• HINT: At The Grand Canyon
DNA Molecule
• The Impossibility of Information
The DNA molecule is one of the
greatest scientific discoveries of all time.
First described by James Watson and
Francis Crick in 1953, DNA is the
famous storehouse of genetics that
establishes each organism's physical
characteristics.
DNA is like a fingerprint because
everyone’s is a little different!
You can tell people apart
by their fingerprints………
and their DNA!
How would the police look at DNA to
figure out who committed a crime?
DNA Molecule
Within cells, DNA is
organized into
structures called
chromosomes.
These chromosomes
are duplicated before
cells divide, in a
process called DNA
replication.