Nucleotides consist of a sugar, phosphate group, and nitrogenous base. Nucleic acids like DNA and RNA are made of nucleotides. DNA contains deoxyribose and thymine, while RNA contains ribose and uracil instead of thymine. DNA replication involves unwinding the DNA double helix, synthesizing new strands based on the existing strands, and rewinding the DNA.

1. End of 12.1 and 12.2

2.  Nucleotides are made
up of 3 things:
1. 5 carbon sugar
2. Nitrogenous
(containing nitrogen)
bases
3. Phosphate group
 Nucleic
Acids (like
DNA and RNA)

3.  The nucleic acid DNA consists of the
following:
1. Deoxyribose- sugar
2. A phosphate group
3. A series of 4 nitrogenous bases: cytosine, adenine, thymine,
guanine

4.  The nucleic acid RNA
consists of the
following:
1. Ribose- sugar
2. A phosphate group
3. A series of 4
nitrogenous bases:
adenine, uracil,
guanine, cytosine

5.  Adenineand Guanine
are considered purine

6.  Thymine, Cytosine,
and Uracil are
considered
pyrimidines

7.  DNA is compared to a
twisted ladder
 Ladder Rails- consist of
alternating deoxyribose
(sugar) and phosphate
group
 A purine base always
bonds with pyrimidine
 Bases are held together
by hydorgen bonds

8.  The direction or
orientation of the
 The carbon in the sugar
molecules are
numbered
 The leading strand
starts with the 3’ (five
prime) end
 The lagging strand runs
in the reverse direction
 This orientation of the

9.  Length of a human
chromosome ranges
from
 If a DNA strand 140
million nucleotides
long
 In order for all of the
DNA to fit into
microscopic cells, the

10.  The phosphate
groups in DNA create
a negative charge
 The structure of DNA
wound around

11.  DNA replication is
considered
semiconservative
replication- because
this process consists

12.  DNA replication
occurs during
interphase of the cell
cycle-
 There are 3 main
stages to
semiconservative
replication:

13.  Helicase-is an
enzyme used to
 When DNA is
unzipped, the
hydrogen bonds
between the bases

14.  DNA polymerase-
enzyme that catalyzes
the addition of
appropriate nucleotides
 There are a plethora of
nucleotides floating in
the cell waiting to be
 DNA polymerase
ensures that each base
binds to its compliment

15.  DNA polymerase adds
the nucleotide bases
to the 3’ end of the
 In this way, the
templates allow
identical copies of

16.  The leading strand is
replicated from 3’ to 5’
end
 The lagging strand is
synthesized
discontinously in
segments called
Okazaki fragments by
the DNA
 The lagging strand is
oriented in the 5’ to 3’

17.  DNA ligase- is an
enzyme that connects
all the fragments of