Download DNA

DNA for Dummies
(and the intellectually astute)
A Dr.
Parrott Production
• Secret of Photo 51:
• Ribosome orchestrates this event
DNA Wrap Basic
DNA Wrap Advanced
Chromosome Packing
DNA Coiling
Replication: DNADNA
• Occurs during S phase of
interphase in reproducing
cells only
• DNA template is copied
complimentarily and semi
conservatively
• Occurs only in the nucleus
Meselson-Stahl Experiment
DNA Replication
Replication Complete
How DNA Replicates
Bidirectional Replication
Make a DNA strand complimentary to the following:
DNA: ATG GTG CAC CTG ACT CCT GTG GAG AAG TCT
DNA: TAC
mRNA:
Amino Acids:
tRNA:
DNA Replication Basic
DNA Replication Fork
DNA Replication
DNA Polymerase
Rep Fork 2
Tran scription: DNAmRNA
• Occurs continually
throughout the cell
cycle with the
exception of mitosis
• Occurs in the
nucleus as
messenger RNA
copies DNA
Transcription Basic
RNA Splicing
Transcription
Transcription Complete
Protein Synthesis
Make a DNA strand complimentary to the following:
DNA: ATG GTG CAC CTG ACT CCT GTG GAG AAG TCT
DNA: TAC
Transcribe the above DNA template into an mRNA:
mRNA: UAC
Amino Acids:
tRNA:
Translation: mRNAprotein
• Occurs continually throughout the cell cycle
• Occurs at the ribosome as it
–
–
–
–
reads the mRNA codons
Matches codons to amino acids
Prompts tRNA to bring a.a.
Attaches a.a. with peptide bonds
DNA to Protein
Translation
• tRNA anticodon is
complimentary to mRNA
codon
• tRNA is specific to the
amino acid it brings
• Peptide bonds connect
amino acids to form
polypeptide (protein)
Translation Basic
Protein Synthesis 2
Translation Advanced
Protein Synthesis
Protein Synthesis
Make a DNA strand complimentary to the following:
DNA: ATG GTG CAC CTG ACT CCT GTG GAG AAG TCT
DNA: TAC
mRNA (codons): UAC
Translate the above mRNA strand into an amino acid
sequence (protein)
Amino Acids: Tyrosine
tRNA (anticodons):
• Watch RNAi Online:
http://www.pbs.org/wgbh/nova/sciencenow/321
0/02.html
Make a DNA strand complimentary to the following:
DNA: ATG GTG CAC CTG ACT CCT GTG GAG AAG TCT
DNA: TAC
mRNA (codons): UAC
Amino Acids: Tyrosine
What are the anticodons on the tRNA for the above strands?
tRNA (anticodons): AUG
To summarize…
Mistakes/Mutations
• Mutation any permanent
alteration in the sequence
of DNA bases
• Point mutations can result
in frameshifts in the
reading frame
• Chromosomal mutations
can result in translocations
Mistakes/Mutations
• Silent mutation
change in n.t. sequence,
but no change in
product
• Missense mutation
swapping of a.a. (sickle
cell anemia, PKU)
• Nonsense mutation
insertion of stop codon
into sequence
Silent Mutation
G
Resources
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Genetics Movies: http://www.dpo.uab.edu/~landrews/genetics.htm
DNA Tutorial: http://www.ncc.gmu.edu/dna/index.htm
Bacterial Replication Animations:
http://www.wwnorton.com/college/biology/mbio/animations/dna_replication.asp
Telomere Synthesis (shortening of linear chromosomes):
http://spine.rutgers.edu/cellbio/assets/flash/tel.htm
Gene Processing
http://highered.mcgrawhill.com/sites/0072437316/student_view0/chapter15/animations.html
Replication Animations: http://highered.mcgrawhill.com/sites/0072437316/student_view0/chapter14/animations.html
Gene Expression Animations:http://highered.mcgrawhill.com/sites/0072437316/student_view0/chapter18/animations.html#
Gene Technology: http://highered.mcgrawhill.com/sites/0072437316/student_view0/chapter16/animations.html