History of Genetics/ INTRO TO DNA

(1) Gregor Mendel “The Father of Genetics” A Monk: Studied pea plants in in a garden Discovered dominant and recessive traits http://www.nlm.nih.gov/visibleproofs/galleries/technologies/dna.html

Created images of the DNA molecule that showed its spiral shape. (2) Rosalind Franklin Created images of the DNA molecule that showed its spiral shape. http://profiles.nlm.nih.gov/KR/B/B/J/N/ http://www.accessexcellence.org/RC/AB/WYW/wkbooks/SFTS/SFTSg/1.jpg

(3) James Watson & Francis Crick These two scientists discovered the complete structure of DNA “The Double Helix” http://www.achievement.org/autodoc/photocredit/achievers/wat0-001

The Structure of DNA

(4) Shape DNA has a double helix shape If you took a ladder and twisted it, it would look like DNA Helix = Spiral

Composition

(5) 1. DNA is made up of phosphates, sugars, and bases (purines and pyrimidines)

(5) 2. A nucleotide is made up of 1 sugar, 1 phosphate and 1 base (Circle a nucleotide on your paper!)

A Nucleotide PHOSPHATE BASE SUGAR

(5) 3. The nucleotides are connected together by the phosphate and the sugar (Think: Sugars and Phosphates = “Side Poles” of the Ladder)

"Side Poles“ "Side Poles" Sugar and Phosphate "Side Poles“

A T G G

“Between “ Bases “Between “

When the bases pair together, they form a Double Helix. (5) 4. When the bases pair together, they form a Double Helix. Purines Pair With Pyrimidines Adenine Pairs With Thymine Guanine Cytosine

A T G G

A C T T C G A T C G