Warm Up Take 2-3 minutes to review your notes over DNA/RNA structure and function to be ready for a short quiz!

Overview of DNA (Deoxyribonucleic Acid) EQ: What is DNA? What is DNA made of? What is the function of DNA? What is a gene? What is a genetic code?

DNA is a complex molecule (polymer), found in ALL living things Eukaryotic: animals, plants, fungi, protists – DNA in NUCLEUS Prokaryotic – bacteria – NO NUCLEUS Do nonliving things have DNA?

DNA is a complex molecule (polymer), found in ALL living things Eukaryotic: animals, plants, fungi, protists – DNA in NUCLEUS Prokaryotic – bacteria – NO NUCLEUS Do nonliving things have DNA? Some viruses: bacteriophage

DNA is a nucleic acid so it is made of nucleotides. (Monomers) Nitrogenous base pairs Deoxyribose Sugar Phosphate Group Nucleotide (monomer) – all 3 parts

Chromosomes are super coiled DNA Nucleus Double helix Gene – section of DNA which codes for a specific protein that codes for a trait Base pairs – fit like puzzle pieces Genetic code = sequence (order) of nitrogen bases (A,T,C,G)

DNA Function: Stores genetic information, Carries the genetic CODE (instructions) for making proteins DNA determines an organisms traits by controlling the synthesis of proteins. Ex height, hair color Proteins-  Traits Hereditary material – passed on to offspring Blueprint for LIFE

DNA Replication EQ: When and how does DNA make a copy of itself? Why is DNA replication important?

What do you think is happening in this picture?

Why does DNA need a copy? Cells divide for an organism to grow or reproduce; every new cell needs an identical copy of the DNA to know how to be a cell

When does DNA make a replica of itself? Right before a cell division

STEPS to DNA replication (duplication)

1. An enzyme, helicase unwinds and “unzips” DNA by breaking weak hydrogen bonds between base pairs “Replication fork” forms

2. An enzyme, DNA polymerase, adds free-floating complimentary nucleotides to each strand in a 5’ to 3’ direction. An enzyme, ligase, joins the nucleotides together (GLUE). “Matching Up”

3. Two new genetically identical DNA molecules are formed ½ - NEW ½ - from Original Old strand New Strand

4. Two new genetically identical DNA molecules rewind