2. What is DNAWhat is DNA
DNA is found in the cells of all livingDNA is found in the cells of all living
things.things.
DNA contains all of the genetic informationDNA contains all of the genetic information
that makes you who you are and everythat makes you who you are and every
individual organism has unique DNA like aindividual organism has unique DNA like a
finger print.finger print.
All humans share 99.9% the same DNAAll humans share 99.9% the same DNA
3. Nucleic AcidsNucleic Acids
Function of DNAFunction of DNA ββ
Store and transmit hereditary informationStore and transmit hereditary information
DNA stands forβ Deoxyribose nucleic acidDNA stands forβ Deoxyribose nucleic acid
4. DNADNA
GeneGene β is a region ofβ is a region of
DNA that codes for aDNA that codes for a
specific trait.specific trait.
ExampleExample
Blue eyesBlue eyes
Brown hairBrown hair
Skin colorSkin color
6. DNADNA
DNA is made out ofDNA is made out of
22 long chains oflong chains of
nucleotides.nucleotides.
Nucleotides are madeNucleotides are made
out of 3 moleculesout of 3 molecules..
1. deoxyribose β1. deoxyribose β
sugar moleculesugar molecule
2. phosphate group β2. phosphate group β
contains phosphatecontains phosphate
(P)(P)
7. DNADNA
3. nitrogen-containing3. nitrogen-containing
base β containsbase β contains
nitrogen (N)nitrogen (N)
Adenine (A)Adenine (A)
Guanine (G)Guanine (G)
Cytosine (C)Cytosine (C)
Thymine (T)Thymine (T)
The nitrogen baseThe nitrogen base
gives a nucleotide itsgives a nucleotide its
name.name.
8. Structure of a DNA NucleotideStructure of a DNA Nucleotide
9. DNA Nucleotide StructureDNA Nucleotide Structure
Since all 4Since all 4
nucleotides (A, T, C,nucleotides (A, T, C,
G) are made out ofG) are made out of
the same three thingsthe same three things
(sugar, phosphate,(sugar, phosphate,
and nitrogen base),and nitrogen base),
nucleotides arenucleotides are
named by theirnamed by their
nitrogen base.nitrogen base.
10. DNADNA
The DNA molecule model was proposedThe DNA molecule model was proposed
by James Watson and Francis Crick.by James Watson and Francis Crick.
11. Double HelixDouble Helix
The sugar and phosphateThe sugar and phosphate
make up the backbone ofmake up the backbone of
DNA and the nitrogenDNA and the nitrogen
bases make up the insidebases make up the inside
rungs (like a ladder)rungs (like a ladder)
Complementary BaseComplementary Base
Pairing: certain basesPairing: certain bases
(nucleotides) always(nucleotides) always
pair with each otherpair with each other
A with TA with T
G with CG with C