DNA Replication Standard 3.1.1 Explain the double-stranded, complimentary nature of DNA as related to its function in the cell.

Making a copy of DNA DNA is copied before cell division during what part of the cell cycle? What is the monomer (building blocks) of DNA? What Complementary base pair binds with Guanine?

DNA Replication DNA replication is the process by which DNA is copied in a cell before a cell divides. DNA will separate into 2 strands Replication begins with the separation of the DNA strands by helicases. Then, DNA polymerases form new strands by adding complementary nucleotides to each of the original strands through base-pairing. (Chargaffs Rule) You need to unzip the dna before you can copy it Polymerase reads dna Whats in. front is what is being made

DNA Replication Each new DNA molecule is made of one strand of nucleotides from the original DNA molecule and one new strand. This is called semi- conservative replication.

Example: TACGTT – Old DNA strand ATGCAA – New DNA strand After DNA is replicated, DNA will have 1 old strand and 1 new strand

Review! What catalyzes the break up of the hydrogen bonds between strands? DNA strands run in the same/opposite direction. Helicase – anything ending with –ase is an enzyme DNA strands run in the opposite (anti parallel) direction.

Errors during Replication Changes in DNA are called mutations. DNA proofreading and repair prevent many replication errors. Unrepaired mutations in body cells that affect genes that control cell division can cause diseases such as cancer. Unrepaired mutations in sex cells (eggs and sperm) can cause diseases genetic diseases or birth defects.

Where does DNA replication occur in the cell Where does DNA replication occur in the cell? Eukaryotes vs Prokaryotes During which part and phase of the cell cycle does DNA replication occur?