DNA

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• DNA

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Traits

• A physical feature, or characteristic, a living
  thing can pass on to its young.
• Ex. Blood type, Eye color, Hair color, Facial
  features, and your body build

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Genes

• Coded info that determines traits.
• A region of DNA that controls a hereditary
  characteristic.

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Chromosomes

• carries the genes that control traits.

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DNA Deoxyribo Nucleic acid
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Structure of DNA
Double Helix
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What are the building blocks?

• Nucleotides joined by strong
  covalent bonds
• Nucleotides composed of
• Phosphate group
• Deoxyribose 5 carbon sugar
• One of four Nitrogenous bases
• Adenine
• Thymine
• Guanine
• Cytosine

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Base Pairing Rules

• Adenine Thymine
• Guanine Cytosine

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Functions of DNA

• Replication DNA makes DNA
• Transcription DNA makes RNA
• Translation RNA makes Proteins

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DNA Replication

• The helix unwinds
• DNA unzips - nucleotides separate as
  hydrogen bonds break
• Free nucleotides base pair with both nucleotide
  chains
• 2 identical DNA molecules result

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DNA Replication                               
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• Leading Strand continuous replication
• Lagging strand discontinuous replication

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figure 11-07b.jpg
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Semi Conservative Replication
   

• Each old DNA strand gets a new strand

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DNA vs. RNA

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DNA VS. RNA
Deoxyribose Sugar Ribose
2 Strands 1
A, T, C, G Bases A, U, C, G
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Transcription

• DNA unwinds and unzips.
• RNA nucleotides base pair with the DNA master
  strand
• Uracil bonds with Adenine
• Cytosine with Guanine.
• RNA strand separates and moves to the cytoplasm
• DNA zips back up

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Reverse Transcription

• HIV retrovirus
• Makes DNA replica of its own RNA
• Viral DNA joins normal DNA of host
• Directs production of new virus particles

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RetroTranscription.jpg? (
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3 Types of RNA

• mRNA messenger RNA
• tRNA transfer RNA
• rRNA ribosomal RNA

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mRNA

• Messenger RNA single strand coded from the DNA
  master strand.
• Contains a three base sequence codon
• Codon codes for a specific amino acid

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tRNA

• Transfer RNA contains sequence of three bases
  anticodon
• anticodon which carry a specific amino acid to
  the mRNA

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rRNA

• Ribosomal RNA located in the ribosomes

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Translation

• The mRNA attaches to a ribosome.
• mRNA contains codons
• (3 nucleotides that code for 1 amino acid)
• The tRNA contain three opposite letters called
  the anticodon.
• tRNA carries an amino acid at the other end.
• Anti codons base pair with codons
• Amino Acids covalently bonded to each other
• tRNA is released to get more Amino Acids

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.                                              
                                                  
                                         
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UUUUUCUUAUUG PhenylalaninePhenylalanineLeucineLeucine UAUUAC TyrosineTyrosine
UUUUUCUUAUUG PhenylalaninePhenylalanineLeucineLeucine UAAUAG None (stop signal)None (stop signal)
CUUCUCCUACUG LeucineLeucineLeucineLeucine CAUCAC HistidineHistidine
CUUCUCCUACUG LeucineLeucineLeucineLeucine CAACAG GlutamineGlutamine
AUUAUCAUAAUG IsoleucineIsoleucineIsoleucineMethioninie (start codon) AAUAAC AsparagineAsparagine
AUUAUCAUAAUG IsoleucineIsoleucineIsoleucineMethioninie (start codon) AAAAAG LysineLysine
GUUGUCGUAGUG ValineValineValineValine GAUGACGAAGAG Aspartic AcidAspartic AcidAspartic AcidAspartic Acid
UCUUCCUCAUCG SerineSerineSerineSerine UGUUGC CysteineCysteine
UCUUCCUCAUCG SerineSerineSerineSerine UGA None (stop signal)
UCUUCCUCAUCG SerineSerineSerineSerine UGG Tryptophan
CCUCCCCCACCG ProlineProlineProlineProline CGUCGCCGACGG ArginineArginineArginineArginine
ACUACCACAACG ThreonineThreonineThreonineThreonine AGUAGC SerineSerine
ACUACCACAACG ThreonineThreonineThreonineThreonine AGAAGG ArginineArginine
GCUGCCGCAGCG AlanineAlanineAlanineAlanine GGUGGCGGAGGG GylcineGylcineGylcineGylcine
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Central DogmaDNA --------------------?RNA
------------------?Protein
transcription translation

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