1. DNA Structure Analysis Questions Answered
The twisted ladder structure of DNA is called a Double Helix.
The backbone of DNA is made up of deoxyribose sugar and phosphate group.
The ladder-like rungs of DNA are made up of nitrogenous bases.
Adenine always pairs up with Thymine.
Cytosine always pairs up with Guanine.
A nucleotide is the basic building block of DNA. A nucleotide is made up of one deoxyribose sugar, one phosphate group, and one nitrogenous base.

2. DNA Replication

3. DNA Packaging
A cell’s nucleus contains chromosomes made up of DNA.

4. Each nucleosome consists of DNA wound around histones
Chromatin Fibers
Each super coil is made up of coils. A coil is a chain of beadlike structures called nucleosomes
Each nucleosome consists of DNA wound around histones
Each chromatin fiber is a tightly wound supercoil

5. DNA replication
Before a cell divides, it duplicates its DNA in a copying process called replication
this process insures that each resulting cell receives a complete set of DNA molecules

6. During replication, the DNA molecule separates into two strands, then produces two new complementary strands following the rules of base pairing. Each strand of the double helix of DNA serves as a template for a new strand

7. DNA Replication
In Eukaryotic Cells replication occurs in hundreds of places at once
Replication proceeds in both directions until each chromosome is completely copied
The places where separation and replication occur are called replication forks

8. Creating a New Strand ATGCAA
Two strands of the double helix separate allowing two replication forks to form
Each new strand forms following the rules of base pairing. For example:
The original strand has the bases: TACGTT
What would the complementary strand be?
ATGCAA

9. CCGTACTTACG GGCATGAATGC
The result is two DNA molecules identical to each other and to the original
NOTE: each DNA molecule will have one original strand and one new strand.
More practice. Create the complementary strand
CCGTACTTACG
Answer
GGCATGAATGC

10. How Replication Occurs
DNA replication is carried out by a series of Enzymes
The enzymes “unzip” a molecule of DNA by breaking the hydrogen bonds between the base pairs
DNA polymerase joins individual nucleotides to produce a DNA molecule and proofreads each new DNA strand

11. Placed on the same page as your notes
Glue the picture of DNA replication into your notes. Copy diagram 1 into your notes. The diagram shows one side of a strand of DNA. Create the complementary strand of DNA that would be made by the process of replication.
Diagram 1