Warm up 11/21
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What
RNA?
What
What
What
Quiz
are 3 differences between DNA &
is a codon?
is the Start Codon (or amino acid)?
is the final product of translation?
◦ Moved to Friday Start of Class
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Exam: Tuesday Nov. 26
◦ Intervention Today 2:45-3:30 pm &
Friday 6:50- 7:35 am
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Notes: Mutation Preview
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Errors in Replication
● Replication is extremely accurate, 1 error occurs
for every billion nucleotides!!!
~equivalent to typing a book 1000
times and leaving only one error
● This is possible because
proofreading enzymes follow the
polymerase checking for errors
Cancer: Mutation
that has lead to
uncontrolled cell
reproduction.
● Mutation = a change in the
nucleotide sequence of DNA
● Some mutations are silent, others
alter a gene’s function or may halt cell
functions
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Mutations: Some mutations affect a single
gene, while others affect an entire
chromosome.
A mutation is a change in an organism’s
DNA.
 Many kinds of mutations can occur,
especially during replication.
 Ex/ A point mutation substitutes one
nucleotide for another.

mutated
base
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Types of Mutations
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Point Mutation
◦ Substitution: One Nucleotide gets mixed up for
another.
◦ Most of the time this is OK
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Frameshift Mutation
◦ Insertion: A nucleotide is inserted in the
sequence.
◦ Deletion: A nucleotide is deleted from the
sequence
◦ This can be bad because every codon after the
frameshift is misread.
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What does the following say?
The quckr edf oxj umpedo vert hel azyb
rownd og.
 The qucck red fox jumped over the lazy
brown dog.
 The quick red fox jumped over the lazy
brown dog.
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Mutations may or may not affect
phenotype.
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Some gene mutations change protein
◦ A mutation may cause a premature stop codon.
◦ A mutation may change protein shape or the
active site.
◦ A mutation may change gene regulation & be
given to offspring.
blockage
no blockage
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Classwork:
◦ IT’S ALL IN THE RECIPE
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HW:
◦ DNA Book
 Pages 5-6 Due Friday
◦ Study guide (due Monday)
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Quiz
◦ Moved to Friday Start of Class

Exam: Tuesday Nov. 26
◦ Intervention Thursday 2:45-3:30 pm &
Friday 6:50- 7:35 am
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5
points of Lab Extra Credit:
◦ Central Dogma of Molecular Biology
Lab
◦ Due on Tuesday
◦ Lab Manual p 43-46
Extra Credit
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