2. Primary Roles of DNA
Store Information
Copy Information
– A cell must make a complete copy of its
DNA before the cell divides
Transmit Information
– DNA molecules must be carefully sorted
and passed along when cells divide
3. Vocabulary
Nucleic acid – molecule that is
essential for life
– Long molecule found in a cell’s
nucleus
– Made of smaller subunits
– Examples are DNA and RNA
4. Vocabulary (cont.)
Nucleotides
–Have 3 parts
A 5-carbon sugar (deoxyribose or
ribose)
A phosphate group
A base that contains Nitrogen
–Adenine, Guanine, Cytosine,
Thymine
5. Structure of DNA
Nucleic acid made of
nucleotides
Double helix model
– Looks like a twisted ladder
Base pairing – bonds in
DNA can form only
between adenine and
thymine or between
guanine and cytosine
6. Structure of DNA
Nucleic acid made of
nucleotides
Double helix model
– Looks like a twisted ladder
Base pairing – bonds in
DNA can form only
between adenine and
thymine or between
guanine and cytosine