1. Deoxyribonucleic Acid
BIOLOGY 12
Deoxyribonucleic Acid

2. Amazing Facts about DNA
DNA has a width of 2nm, with the bases 0.34nm apart (1nm = cm)
the human genome consists of an estimated 3 billion base pairs
it would take a person typing 60 words per minute, 8 hours a day, for 50 years to type out the human genome

3. the DNA in one human cell would have a total length of 1.7 meters
if you unwrap all the DNA in all of your cells, it would reach the moon 6000 times
red blood cells are the only cells in the human body that do not have DNA

4. DNA Deoxyribonucleic Acid a double stranded polymer of nucleotides
carries that genetic information of an organism

5. Nucleotides 3 Parts of a Nucleotide: deoxyribose sugar phosphate group
nitrogenous base
Thymine
Adenine
Cytosine
Guanine

6. Nucleotides

7. Nitrogenous Bases Purines: characterized by a double ring
Adenine and Guanine
Pyrimidines:
characterized by a single ring
Thymine and Cytosine

8. Nitrogenous Bases
Purines
Pyrimidines

9. Base Pairings Adenine and Thymine Cytosine and Guanine
Purines only pair with Pyrimidines.
Only pair this way because of bonds.
A and T form 2 hydrogen bonds.
C and G form 3.
page 210 and 213

10. Base Pairings

11. DNA Structure the deoxyribose sugar is a five-carbon ring
each carbon is numbered 1 prime (1’) through to 5 prime (5’)
the nitrogenous base is attached to the 1’ carbon by a glycosyl bond
the phosphate group is attached to the 5’ carbon by an ester bond

12. DNA Structure DNA is a double helix
backbone is composed of the sugar and phosphate groups
stabilized by hydrogen bonds between the bases

13. DNA Structure each strand has a direction DNA strands are antiparallel
the direction of one strand is opposite to the direction of the other strand
5’ end – terminates with a phosphate group
3’ end – terminates with a hydroxyl group

17. Questions
Page 216 #2, 3, 5, 6, 7