What is DNA and why is it important?

Oh yeah, mitosis ends with 2 genetically identical cells! DNA DNA stores genetic information DNA tells cells what to do and which proteins to make. S-phase makes sure that the same DNA is shared with new cells during mitosis. Oh yeah, mitosis ends with 2 genetically identical cells!

Oh yeah, meiosis ends with 4 genetically different cells! DNA Oh yeah, meiosis ends with 4 genetically different cells! Transmits and conserves DNA from one generation to the next. The changes occur during crossing over of meiosis; this is how one person can carry DNA from very many different ancestors.

DNA – why else is it important? DNA can help research disease. You read about transformation in bacteria. Transformation is when DNA from one organism is placed into bacteria

Structure of DNA Can you remember which monomer builds DNA? Can you remember the 3 parts of a nucleotide? nitrogenous

Chargaff’s Rule A=T C=G

Each base pair is held together by Double Helix Because of pictures from a woman named Rosalind Franklin, James Watson and Frances Crick figured out that DNA is in the shape of a double helix. Each base pair is held together by hydrogen bonds Base Pairs AT CG

DNA Replication Different for Prokaryotes and Eukaryotes Eukaryotes Many different starting points! Prokaryotes Just one starting point

2 steps of DNA Synthesis DNA polymerase is the enzyme that builds and checks the DNA Helicase is an enzyme that unzips the DNA Helicase

Can you find the 2 enzymes that help DNA replicate?

Hydrogen bonds DNA Polymerase DNA Polymerase