NUCLEIC ACID NOTES
Nucleic Acid Structure
__________________ are the chemical link between generations dating back to the beginning of life on
earth.
A nucleic acid is a complex macromolecule that stores information in cells in the form of a
______________.
Nucleic acids are made of long chains of _______________________
Nucleotides are made of three components:
1. _________________________
2. _________________________
3. _________________________
Examples of nucleic acids are :
1. _____________
2. _____________
DNA = _____________________
it’s components are:
1. _______________________
2. _______________________
3. _______________________
_____________________ and _______________________ proposed that DNA has a specific pairing
between nitrogen bases:
1. ______________________
2. ______________________
3. ______________________
4. ______________________
adenine ---_________________
_________________ --- cytosine
Watson and Crick also said the paired nitrogen bases formed ____________ long strands of nucleotides
that compliment each other.
___________________ are connected between __________________ and _________________
They declared, “This structure is a “________________________”
DNA forms ___________________________, units of genetic information which pass from parent to
offspring.
If you unraveled all your chromosomes from all of your cells and laid out the DNA end to end, the strands
would stretch from the Earth to the Moon about ___________________.
RNA has a different ________________ than DNA
RNA = ________________________________
It’s components are :
1. ___________________________
2. ___________________________
3. ___________________________
RNA also has different bases that DNA
adenine --- ________________
________________ --- guanine
RNA is also ____________ stranded, not _______________ stranded like DNA.
DNA Replication
I. Why Must DNA Replicate?
Every time a cell divides, it must first make a copy of it’s ______________. Therefore, each cell
can have a _____________ _______ of chromosomes.
Without replication, species could not survive and individuals could not successfully grow and
________________________.
II. How DNA Replicates
DNA is a molecule composed of ______ strands, each consisting of a sequence of
____________________________.
The order of the _______________ ___________ on one strand mandates the sequence of bases
on the ____________________strand.
If you know the bases on one strand, you can predict which bases will occur on the
complementary strand.
A
G
T
C
C
C
T
-----------------------------
During Replication each strand serves as a ___________________ to create a new strand.
III. Steps In Replication
1) ______________ break down the ________________ bonds between the two DNA strands,
unzipping the molecule
2) As the DNA unzips, free nucleotides (from surroundings in the nucleus) bond to the single
strands by _________ ___________________ (A-T, G-C)
3) Another Enzyme bonds the new nucleotides into a __________________
** The result of this process is the formation of TWO DNA molecules, each _________________
to the original molecule.