Download DNA Replication - ms. velasco`s laboratory

Essential Question: How does DNA make
copies of itself?
Let Review…
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DNA = DeoxyriboseNucleic Acid
DNA is made of Nucleotides
Each nucleotide has a phosphate sugar and nitrogen base
There are four different Nitrogen bases:
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Adenine
Thymine
Cytosine
Guanine
 Adenine pairs with Thymine (A with T)
 Cytosine pairs with Guanine (G with C)
Vocabulary
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 DNA Replication: making a copy of a chromosome
during MITOSIS
 DNA Helicase: unwinds the double helix creating
two separate DNA strands
 DNA Polymerase: joins individual nucleotides to
produce the second complementary strand of DNA
 Only move in ONE direction, 5’ to 3’, so DNA strands
are made going in opposite directions.
Steps of DNA Replication
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1. DNA / Chromosomes are unwound and unzipped
by DNA helicase
2. Free nucleotides in the nucleus are joined to both of
the separated strands of DNA polymerase
3. This continues until the DNA completely unzips
and you have 2 exact copies of DNA /
Chromosomes
DNA Replication Foldable
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1. Fold paper so that the notes are on the back and the DNA
molecule is on the front
 MAKE SURE YOUR DNA MOLECULE IS FACING UP
2. Label one side with DNA molecule with nitrogen bases (A,T,C,G)
3. Then write the corresponding letter on the opposite side
(A with T and C with G)
4. Cut between the 6th and 7th nitrogen base from the bottom and
tape the top flaps together
5. On the unzipped DNA strand (the part you didn’t tape closed)
copy the same code written on the front flap
6. Then draw in the new complimentary strands to the unzipped
DNA
7. Color your nitrogen bases.
8. Label the first two steps on DNA replication from your notes on
the foldable.
 DNA is always replicated
from the 5’ end to the 3’
end
 The two unzipped sides
of the DNA strand are
replicated in opposite
directions (one moves left
across the strand and one
moves right across the
strand)
Vocabulary
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 Leading strand: the
strand that is copied
continuously
 Lagging strand: the
strand that is copied in
separate fragments
 Okizaki Fragments: the
name of the fragments
present in the lagging
strand
DNA Replication Foldable
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1. Fold paper so that the notes are on the back and the DNA molecule is on the front
 MAKE SURE YOUR DNA MOLECULE IS FACING UP
2. Label one side with DNA molecule with nitrogen bases (A,T,C,G)
3. Then write the corresponding letter on the opposite side
(A with T and C with G)
4. Cut between the 6th and 7th nitrogen base from the bottom and tape the top flaps together
5. On the unzipped DNA strand (the part you didn’t tape closed) copy the same code written
on the front flap
6. Then draw in the new complimentary strands to the unzipped DNA
7. Color your nitrogen bases.
8. Label the first two steps on DNA replication from your notes on the foldable.
9. Label 3’ and 5’ ends of the DNA strand.
10. Label the leading strand and lagging strand on the foldable