DNA REPLICATION 1 WHAT DOES IT MEAN TO
- Slides: 18
DNA REPLICATION
1. WHAT DOES IT MEAN TO REPLICATE? Replicate means to duplicate or copy.
DNA REPLICATION SUMMARY When one DNA molecule is duplicated (copied) to make two new molecules DNA. Start with one molecule of DNA. End with two new molecules of DNA. Exact Copies
WHAT ORGANISMS GO THROUGH DNA REPLICATION? All living things go through DNA Replication.
PURPOSE Why would your cells need to make copies of its DNA?
PURPOSE OF DNA REPLICATION DNA replication occurs when new or more cells are needed. - Asexual (mitosis) Examples: -Sexual (meiosis) Examples: Everything in the cell is replicatedincluding DNA
DNA REPLICATION: STEP BY STEP 3 steps to DNA replication 1. 2. 3. Unzip/Separate Building/Adding 2 New Copies Some steps require enzymes (proteins) to speed up the process
DNA REPLICATION IN REAL TIME http: //www. youtube. com/watch? v=WNq. Msn 45 DE&safety_mode=true&persist_safety_m ode=1&safe=active
STEP ONE: SEPARATE OR UNZIP Description: DNA is separated into two strands Materials: An enzyme: DNA Helicase “unzips” the DNA
STEP TWO: BUILDING Description: Nucleotides are added to the both of the two separated strands Two Materials: -A. An enzyme: DNA Polymerase adds nucleotides to the old strand. -B. Free Nucleotides
STEP THREE: NEW COPIES Description: Two new copies (exact duplicates) are made.
SUMMARY 1. 2. 3. Separate Build Two new copies
WHICH MODEL OF DNA REPLICATION DO YOU THINK DNA GOES THROUGH?
DNA REPLICATION MODEL DNA replication is known as semi-conservative What does “semi-” mean? -half or partial What does “conservative” mean? -using old materials, not changing
DNA REPLICATION IS SEMI-CONSERVATIVE BECAUSE…. The 2 new molecules of DNA are each made of: -one old “parent” strand -one newly made “daughter” strand
ACCURACY OF REPLICATION �This replication process only makes a mistake once every billion nucleotides �DNA polymerase has a built in proofreader (spell-check) that checks for mistakes and fixes them immediately!
WHICH MODEL OF DNA REPLICATION DO YOU THINK DNA GOES THROUGH?
TABLE CHALK REVIEW: DIRECTIONS 1. 2. 3. Name three steps 2. Draw a diagram 3. Label the “materials” 4. Show me to get credit Step 3: Use different colors to show the difference between the parent strand the new daughter strand of DNA 1.