Bellwork: 1/11 Put your phone up Week 1/7-1/11 How do you think DNA replicates? Why does DNA need to duplicate itself? What type of bonds hold the nitrogenous base pairs together?
Today: Finish DNA Paper Model Unit 5, pt. 3 Notes Review
Materials Unit Book DNA Model
This Week: Monday: DNA Video Tuesday: Finish Video, Unit 5 pt. 1 & 2 Notes, Start DNA Model Wednesday: DNA Model Friday: Pt. 3 Notes & Review
Next Week: Monday: DNA Lab Tuesday: DNA Packet Wednesday: Quiz, Unit 5 pt. 4 Notes Friday: Finish Notes, Review, Packet
Homework
DNA Paper Model Color & cut carefully Build model Get checked by me BEFORE you glue/tape Tape model to other classmates’ model Complete questions…in complete sentences PROJECT GRADE!!!
Unit V: Molecular Genetics
Part III: DNA Replication
Quick Review A pairs with T C pairs with G Hydrogen bonds hold the bases together One DNA molecule = two strands Antiparallel (opposite)
Key Factors Replication Forks: sites where separation & replication of DNA occur DNA Polymerase: Joins nucleotides to produce new DNA molecule “Proofreads” each new strand to make sure that each new strand of DNA is identical to the original
What is DNA Replication? A process where DNA is copied In what phase of Interphase is DNA replicated?
When? DNA replication occurs during the S phase in Interphase Is interphase apart of mitosis?
Where? In eukaryotes, DNA replication occurs in the NUCLEUS In prokaryotes, DNA replication occurs in the CYTOPLASM
Steps of DNA Replication
Step 1 DNA helicase “unzips” the DNA molecule into two strands Breaks the Hydrogen bonds between the nitrogenous bases Forms replication fork
Step 2 Each separated strand now serves as a template to produce new strands! Primase = enzyme that acts as the “green light” for replication to start
Step 3 3. DNA Polymerase attaches to the single strands Help make two new DNA strands by base pairing A-T, G-C New double strands of DNA are IDENTICAL
Step 4 4. DNA Ligase ”glues” the new DNA molecules together Forms Hydrogen bonds between the nitrogenous bases
Results In… 2 IDENTICAL DNA molecules Each molecule is made up of one old strand and one new strand https://www.youtube.com/watch?v=5qSrmeiWsuc
Review
What macromolecule is DNA?
DNA is a chain of _________________
What 3 things make up a nucleotide?
What makes up the DNA backbone?
What makes up the DNA backbone?
What are the 4 bases in DNA?
What bases pair together?
What bonds hold base pairs together?
What is the shape of DNA called?
Who got credit for discovering the shape of DNA?
Who took xray images of DNA?
Where is DNA found in eukaryotic cells?
Exit ?s What enzyme is responsible for unzipping the DNA strands? What enzyme is responsible for reforming the hydrogen bonds between the bases in the new DNA strands? What enzyme uses base pairing to help make new DNA strands?