Bell Ringer: 3A 1.How many strands are in a DNA molecule? 2.What 3 parts make up a nucleotide. 3.What base will pair with Adenine? 4.What base will pair with Guanine? 5.Which phase of cell division does the DNA replicate itself?

Bell Ringer: Get Out All 5 Notepacks! 1.How many strands are in a DNA molecule? 2.If nucleic acid (DNA) is the polymer, what is it’s monomer. (hint: from Unit 2 Macromolecules Notepage) 3.What 3 parts make up a nucleotide. 4.What is Chargaffs rule? 5.What did Watson and Crick call the DNA structure? 6.Which phase of cell cycle does the DNA replicate itself? (hint: from Unit 3a Mitosis) 7.What is an Enzyme ? (hint: from Unit 2 Chemical Reactions)

Joke of the Day:

What kind of video games do dogs play?

Unit 4: DNA Replication

It’s Complementary Dear Watson!! Watson and Crick discovered that DNA is made up of two complementary strands. The strands are considered complementary because each strand can be used to make the other strand.

The Cell Cycle Revisited Remember: Before Cell Division begins, the cell replicates its DNA during the S phase of Interphase. M phase G 2 phase S phase G 1 phase

DNA Replication Definition: The process where a DNA molecule is copied. Why? So that after cell division each new daughter cell can have an identical copy of DNA.

The DNA Replication Process 1.The enzyme DNA Helicase separates the DNA Molecule into two strands by breaking the Hydrogen bonds. 2.The enzyme DNA Polymerase aids in the replication process and proofreads the new strand. 3.The result is 2 DNA molecules each with one old strand and one new strand.

DNA polymerase 2 Original Strands 1 New Strand 1 Original Strand 1 New Strand 1 Original Strand

DNA Replication Practice A G T A C A T C G G A C T T C G C T C A T G T A G C C T G A A G C G