DNA Replication AP Biology Ch 16.2

Remember… You started as one cell with one set of DNA Now you are trillions of cells! Each cell has the same DNA

How does each cell get DNA? DNA Replication Process by which DNA is copied Occurs in all living organisms Many enzymes are used!

DNA structure

DNA structure

Step 1: DNA Replication Start with one complete strand of DNA Template Strand Parent Strand

Step 2: DNA Replication Topoisomerase unwinds DNA

Step 3: DNA Replication Helicase Unzips template strand at H bonds

Step 4: DNA Replication Replication fork forms

Step 5: DNA Replication DNA polymerase Finds starter sequence Adds free DNA nucleotides Checks the sequence Makes repairs

Step 6: Okazaki Fragments DNA is antiparallel One strand of DNA: synthesized continuously The other strand of DNA: is synthesized in segments (O.F.)

Step 7: DNA Replication DNA Ligase Connects Okazaki fragments

Step 8: DNA Replication Two identical strands of DNA are formed Each strand has a parent and daughter strand

The Others

Replication Animations PBS: http://www.youtube.com/watch?v=5VefaI0LrgE St. Olaf: http://www.stolaf.edu/people/giannini/flashanimat/molgenetics/dna-rna2.swf