1. 3 Question Challenge – 1/4 1. The complementary base to Adenine in DNA is ________? 2. The 3 parts of a nucleotide are a nitrogen base (A,T, C, or G); a five carbon (pentose) sugar; and a(n) ___________. 3. If there is 20% G in a cell, what would be the percent of A?

2. DNA Replication

3. DNA Replication is Semiconservative  This means when DNA is copied, the 2 new strands of DNA each contain 1 original side and 1 new side.

4. Steps of DNA Replication 1. The enzyme HELICASE un-zips the DNA strand by breaking HYDROGEN BONDS between bases. 2. The enzyme DNA POLYMERASE adds new COMPLEMENTARY DNA to the original DNA template. 3. This continues until the entire molecule is copied, leaving 2 new identical strands of DNA.

5. DNA Replication 123 DNA Polymerase Helicase