DNA Structure/Function

RECALL … 4 classes of macromolecules –Carbohydrates –Lipids –Proteins –NUCLEIC ACIDS!!! –Subunit: NUCLEOTIDES

Nucleic Acid Examples DNA – deoxyriboNUCLEIC ACID (de – without, oxy – oxygen, ribo – ribose sugar) Store and pass genetic information RNA – riboNUCLEIC ACID Protein synthesis Subunits of DNA/RNA: nucleotides

DNA Very longVery long thin molecule made up of linked nucleotides Double stranded helix –Twisted ladder Determines traits of EVERY LIVING ORGANISM

Nucleotide Structure 3 parts –Sugar (deoxyribose or ribose) –Phosphate (P with oxygens attached) –Nitrogen base Adenine Thymine Guanine Cytosine

Nucleotide Structure 2 classes of nucleotides –Purines Adenine Guanine –Pyrimidines Thymine Guanine

Nitrogen Base Pairing Adenine Thymine 4-eva Guanine Cytosine

Nitrogen Base Pairing Adenine Thymine Guanine Cytosine = Hydrogen Bond

Nitrogen Base Pairing Adenine Thymine CytosineGuanine ThymineAdenine CytosineGuanine AdenineThymine Guanine Cytosine = Hydrogen Bond

Nitrogen Base Pairing Adenine Thymine CytosineGuanine ThymineAdenine CytosineGuanine AdenineThymine Guanine Cytosine

3  5 Each Strand has Opposite Orientations 5  3

Compl-e-ment – complement –To complete, finish, or fill something up NOT this kind… Compl-i-ment - compliment –“You are the coolest student on this planet!”

What is the COMPLEMENTARY DNA STRAND? EXAMPLE 1 3’ end 5’ end ATTGACCATTGATAGCCGAATA TAACTGGTAACTATCGGCTTAT EXAMPLE 2 5’ end 3’ end TCTTCGGAACATTAGTCGAGGC AGAAGCCTTGTAATCAGCTCCG

The “C”s of Genetics DNA ladder DNA double helix Histones (proteins) with DNA coiled around them CHROMATIN

CHROMATID DNA ladder DNA double helix Chromatin Coiled up Chromatin 2 Chromatids

CHROMOSOME Chromatin 2 Chromatids 2 Chromatids = 1 Chromosome

Centromere Holds sister chromatids together in a chromosome