4. DNA discovered: 1953; James Watson, Francis Crick and
Rosalind Franklyn -used x-ray crystallography to see DNA shape
-died at age 38 -used Franklyns to write their paper -received the
Nobel prize in 1962
Slide 7
DNA Structure -Shaped like a twisted ladder -Called double
helix
Slide 8
DNA Structure -Nucleotide: monomer of DNA made of a sugar
(deoxyribose), a base and a phosphate
Slide 9
Bases of DNA Purines (large bases): -adenine (A) -guanine (G)
Pyrimidines (small bases): -thymine (T) -cytosine (C) *Adenine with
thymine *Cytosine with Guanine -bonded with weak hydrogen
bonds
Slide 10
How to Draw DNA
Slide 11
Nucleic Acid Processes: 1.Replication: DNA copying and making
new DNA 2.Transcription: DNA making RNA 3.Translation: RNA
synthesizes proteins
Slide 12
Central Dogma:
Slide 13
DNA Replication -cell divide and must replicate DNA -happens
before mitosis 3 Steps: 1.The enzyme helicase moves over DNA and
unzips it at the hydrogen bonds 2.DNA polymerase (enzyme) moves
along the exposed strand and adds the complimentary nucleotide
3.Two daughter strands are formed
Slide 14
DNA Replication -One mistake for every 10,000 base pairs
-Mutation: a change in nucleotide sequence -Not always bad; some
good; most neutral
Slide 15
DNA vs. RNA Comparison DNA 1.FX: stores genetic information
2.Double helix structure 3.Base: A, C, G, and T 4.Sugar:
deoxyribose RNA 1.FX: synthesizes proteins 2.Single helix structure
3.A,C,G, and Uracil 4.Sugar: ribose
Slide 16
Three Types of RNA 1. Messenger RNA (mRNA): provides the code
for amino acids 2.Transfer RNA (tRNA): carries amino acids to
ribosome 3.Ribosomal RNA (rRNA): unknown function
Slide 17
Transcription: DNA makes RNA 4 Steps: 1.RNA polymerase opens
DNA and adds complimentary RNA nucleotides to the DNA 2.RNA reaches
a stop sequence 3.mRNA leaves the nucleus to build proteins
Slide 18
Translation: protein synthesis Protein: What are they? -amino
acids are the monomers -20 different amino acids -peptide bonds
between amino acids -codon: a three base code on mRNA that codes
for amino acids -each codon is specific for an amino acid
Slide 19
mRNA Coding Chart
Slide 20
Decode the following strand of DNA in mRNA then into a protein
Protein: START- Phe Asn Ala Thr His stop mRNA: AUG UUU AAC GCU ACA
CAC UAA DNA: TAC AAA TTG CGA TGT GTG ATT
Slide 21
Translation: Steps 1.mRNA leaves the nucleus, enters cytoplasm,
attaches to a ribosome. 2.tRNA attaches to the mRNA with an
anticodon, carrying an amino acid 3.Amino acid attaches to a
ribosome and starts the protein. tRNA leaves to get a new amino
acid 4.Ribosome moves down the mRNA picking up a new amino acid at
each codon. 5.Reaches the stop codon and ends translation 6.Protein
is released for a metabolic process.
Slide 22
Slide 23
DNA Technology
Slide 24
The Genome:
Slide 25
- The totality of DNA base pairs in the cells of a species
-exact sequence of DNA bases -All the ACTGs on each chomosome -One
of the greatest discoveries of all time
National Genome Project -Director: Francis Collins -blue print
of human body: the holy grail -12 year project -Fully funded by
U.S. Government -Life changing
Slide 28
How it will change our lives: - Gene screening at an early age
-Know diseases in advance -Designer drugs -Design babies -Genetic
counselors -Lifespan expanded -Genetically modified organisms
Slide 29
Genome is the future of medicine -Pre-treat disease and illness
before it manifests itself -Changed our legal system, medical
science, understanding evolution
Slide 30
DNA Technology and Criminology
Slide 31
Polymerase Chain Reaction -Process of amplifying a sample of
DNA -Uses: criminal convictions, ID human remains, new species,
taxonomy, evolution
Slide 32
Gel Electrophoresis: DNA fingerprinting 1.DNA is put into a gel
2.Stained with methyl or violet 3.Moved through gel with
electricity 4.Separate by size 5.The more matching bands the more
likely a sample and an unknown are related