 Double stranded helix made of nucleotides
 AKA a twisted ladder
 Discovered by James Watson and Francis Crick, Using
x-rays from Rosalind Franklin
 Determines the traits of an organism
 It is the blueprint for proteins
 A gene is a segment of DNA that codes for a specific
protein
 A chromosome is a tightly coiled piece of DNA
 Nucleotides in DNA consist of a phosphate group, a 5
corbon sugar deoxyribose, and a nitrogenous base
 In DNA the bases are:
 Adenine
 Guanine
 Thymine
 Cytosine
 Chargaff’s Rule states that:
 Adenine always bonds to Thymine with 2 hydrogen
bonds
 Guanine always bonds to Cytosine with 3 hydrogen
bonds
 DNA is made and stays in the nucleus in eukaryotic
cells
 In prokaryotic cells DNA is found in the cytoplasm,
not surrounded by a membrane