1. THE FLOW OF GENETIC INFORMATION FROM DNA TO RNA TO PROTEIN

2. I Can…
Describe the locations, reactants, and products of transcription and translation.
Diagram the overall process of transcription and translation.

3. DNA  Proteins  Cells
DNA (genes) has the information to build proteins
proteins
cells
DNA gets all the glory, Proteins do all the work 3

4. How do proteins do all the work
proteins run living organisms
enzymes
control all chemical reactions in living organisms
structure
all living organisms are built out of proteins 4

5. Protein Synthesis: overview
The sequence of DNA determines the sequence of Amino Acids (monomer) that makes up each protein (polymer).
Transcription: synthesis of mRNA under the direction of DNA
Translation: actual synthesis of a polypeptide under the direction of mRNA

6. The Triplet Code
The genetic instructions for a protein/ polypeptide chain are ‘written’ in the DNA as a series of 3-nucleotide ‘words’ called….
Codons: the basic unit of genetic code
Don’t forget!
‘U’ (uracil) replaces ‘T’ in RNA

7. Transcription: Transcription of a gene occurs in three main steps:
Initiation, involving the attachment of RNA polymerase to the promoter and the start of RNA synthesis,
Elongation, as the newly formed mRNA strand grows
Termination, when RNA polymerase reaches the terminator DNA and the polymerase molecule detaches from the newly made mRNA strand and the gene.

8. Transcription: overview

9. 10.10 Eukaryotic RNA is processed before leaving the nucleus as mRNA
Eukaryotic mRNA undergoes processing before leaving the nucleus.
RNA splicing removes introns (intervening sequences) and joins exons (expressed sequences) to produce a continuous coding sequence.
Student Misconceptions and Concerns
• Beginning college students are often intensely focused on writing detailed notes. The risk is that they will miss the overall patterns and the broader significance of the topics discussed. Consider a gradual approach to the subjects of transcription and translation, beginning quite generally and testing comprehension, before venturing into the finer mechanics of each process.
Teaching Tips
• Many analogies can be developed to represent the selective expression of a gene requiring the deletion of introns. Instructors who only assign some modules of a chapter are treating the chapters like sections of exons and introns, portions to be read and portions to be skipped. Alternately, students who highlight a chapter might be thought of as editing the book into exons, portions to be reviewed, and introns, nonhighlighted sections that will not be studied. Both analogies are imperfect, but may still convey the concept of selective reading.
Active Lecture Tips
 See the Media Review: “Learn.Genetics” Genetic Science Learning from the University of Utah on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Baking Cookies Describes the Central Dogma on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Using a Food Analogy to Think About Protein Synthesis on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Students Perform a Protein Synthesis Play on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity. 9

10. Translation
mRNA from nucleus is ‘read’ along its codons by tRNA’s anticodons at the ribosome
Each codon on the mRNA has a complimentary tRNA anticodon (nucleotide triplet)
Each tRNA has been previously linked to an amino acid.

11. Translation continued
Ribosome: site of mRNA codon & tRNA anticodon coupling
P site: holds the tRNA carrying the growing polypeptide chain
A site: holds the tRNA carrying the next amino acid to be added to the chain

13. Translation continued
Initiation: union of mRNA & tRNA
Elongation:
codon recognition
peptide bond formation
Translocation
Termination:
‘stop’ codon reaches ‘A’ site

14. Translation

15. DNA Transcription RNA Codon Translation Polypeptide Amino acid
Figure
DNA
A A A C C G G C A A A A
Transcription
RNA U U U G G C C G U U U U
Codon
Translation
Figure Transcription and translation of codons (partial)
Polypeptide
Amino acid 15

16. Second base of RNA codon U C A G
Figure 10.8a
Second base of RNA codon
U C A G
UUU
UCU
UAU
UGU U C
A G
Phe
Tyr
Cys
UUC
UCC
UAC
UGC U
Ser
UUA
UCA
UAA Stop
UGA Stop
Leu
UUG
UCG
UAG Stop
UGG
Trp
CUU
CCU
CAU
CGU U C
A G
His
CUC
CCC
CAC
CGC C
Leu
Pro
Arg
CUA
CCA
CAA
CGA
Gln
First base of RNA codon
Third base of RNA codon
CUG
CCG
CAG
CGG
AUU
ACU
AAU
AGU U C
A G
Ser
Asn
AUC
lle
ACC
AAC
AGC A
Thr
Figure 10.8a The genetic code used to translate RNA codons to amino acids
AUA
ACA
AAA
AGA
Arg
Lys
AUG
Met or start
ACG
AAG
AGG
GUU
GCU
GAU
GGU U C
A G
Asp
GUC
GCC
GAC
GGC G
Val
Ala
Gly
GUA
GCA
GAA
GGA
Glu
GUG
GCG
GAG
GGG 16

17. Strand to be transcribed
Figure 10.8b-1
Strand to be transcribed
T A C T T C A A A A T C
DNA
A T G A A G T T T T A G
Figure 10.8b-1 Deciphering the genetic information in DNA (step 1) 17

18. Strand to be transcribed
Figure 10.8b-3
Strand to be transcribed
T A C T T C A A A A T C
DNA
A T G A A G T T T T A G
Transcription
RNA
A U G A A G U U U U A G
Figure 10.8b-3 Deciphering the genetic information in DNA (step 3)
Start codon
Stop codon
Translation
Polypeptide
Met
Lys
Phe 18

19. 10.8 The genetic code dictates how codons are translated into amino acids
The genetic code is
nearly universal, in that the genetic code is shared by organisms from the simplest bacteria to the most complex plants and animals.
Student Misconceptions and Concerns
• Beginning college students are often intensely focused on writing detailed notes. The risk is that they will miss the overall patterns and the broader significance of the topics discussed. Consider a gradual approach to the subjects of transcription and translation, beginning quite generally and testing comprehension, before venturing into the finer mechanics of each process.
Teaching Tips
• You may want to note the parallel between the discovery in 1799 of the Rosetta Stone, which provided the key that enabled scholars to crack the previously indecipherable hieroglyphic code, and the cracking of the genetic code in Consider challenging your students to explain what part of the genetic code is similar to the Rosetta Stone. This could be a short in-class activity for small groups.
• The authors note the universal use of the genetic code in all forms of life. The evolutionary significance of this fundamental, universal language is a reminder of the shared ancestry of all life. The universal genetic code is part of the overwhelming evidence for evolution.
Active Lecture Tips
 See the Media Review: “Learn.Genetics” Genetic Science Learning from the University of Utah on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Baking Cookies Describes the Central Dogma on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Using a Food Analogy to Think About Protein Synthesis on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Students Perform a Protein Synthesis Play on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity. 19

20. Figure 10.15-5 A summary of transcription and translation (step 5)
DNA
Transcription
NUCLEUS
mRNA 1
Transcription
RNA polymerase
Translation
CYTOPLASM
Amino acid
Amino acid attachment 2
Enzyme
tRNA
ATP
Initiator tRNA
Anticodon
Large ribosomal subunit
Initiation of polypeptide synthesis 3 U A C
A U G
Start
codon
Small ribosomal subunit
mRNA
New peptide bond forming
Growing polypeptide
Elongation
Figure A summary of transcription and translation (step 5) 4
Codons
mRNA
Polypeptide 5
Termination
Stop codon 20

21. Review of Transcription and Translation

22. I Can…
Describe the major types of mutations, causes of mutations, and potential consequences.

23. 10.16 Mutations can affect genes
A mutation is any change in the nucleotide sequence of DNA.
Mutations can involve
large chromosomal regions or
just a single nucleotide pair.
Student Misconceptions and Concerns
• Beginning college students are often intensely focused on writing detailed notes. The risk is that they will miss the overall patterns and the broader significance of the topics discussed. Consider a gradual approach to the subjects of transcription and translation, beginning quite generally and testing comprehension, before venturing into the finer mechanics of each process.
• Mutations are often discussed as part of evolutionary mechanisms. In this sense, mutations may be considered a part of a creative process. The dual nature of mutations, potentially deadly yet potentially innovative, should be clarified.
Teaching Tips
• A simple way to demonstrate the effect of a reading frame shift is to have students compare the following three sentences. The first is a simple sentence. However, look what happens when a letter is added (2) or deleted (3). The reading frame is reformed into nonsense.
(1) The big red pig ate the red rag.
(2) The big res dpi gat eth ere dra g.
(3) The big rep iga tet her edr ag.
• The authors have noted elsewhere that “A random mutation is like a random shot in the dark. It is not likely to improve a genome any more than shooting a bullet through the hood of a car is likely to improve engine performance!”
Active Lecture Tips
 See the Media Review: “Learn.Genetics” Genetic Science Learning from the University of Utah on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Demonstrating a Frame Shift Mutation on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity. 23

24. 10.16 Mutations within a gene can be divided into two general categories.
Nucleotide substitutions involve the replacement of one nucleotide with another pair of nucleotides.
have no effect at all (silent mutation)
change the amino acid coding (missense mutation) which produces a different amino acid
lead an improved protein that enhances the success of the mutant organism and its descendants,
change an amino acid into a stop codon, (nonsense mutation)
Student Misconceptions and Concerns
• Beginning college students are often intensely focused on writing detailed notes. The risk is that they will miss the overall patterns and the broader significance of the topics discussed. Consider a gradual approach to the subjects of transcription and translation, beginning quite generally and testing comprehension, before venturing into the finer mechanics of each process.
• Mutations are often discussed as part of evolutionary mechanisms. In this sense, mutations may be considered a part of a creative process. The dual nature of mutations, potentially deadly yet potentially innovative, should be clarified.
Teaching Tips
• A simple way to demonstrate the effect of a reading frame shift is to have students compare the following three sentences. The first is a simple sentence. However, look what happens when a letter is added (2) or deleted (3). The reading frame is reformed into nonsense.
(1) The big red pig ate the red rag.
(2) The big res dpi gat eth ere dra g.
(3) The big rep iga tet her edr ag.
• The authors have noted elsewhere that “A random mutation is like a random shot in the dark. It is not likely to improve a genome any more than shooting a bullet through the hood of a car is likely to improve engine performance!”
Active Lecture Tips
 See the Media Review: “Learn.Genetics” Genetic Science Learning from the University of Utah on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Demonstrating a Frame Shift Mutation on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity. 24

25. 10.16 Mutations can affect genes
Nucleotide insertions or deletions of one or more nucleotides in a gene may
cause a frameshift mutation, which alters the reading frame (triplet grouping) of the genetic message,
lead to significant changes in amino acid sequence, and
produce a nonfunctional polypeptide.
Student Misconceptions and Concerns
• Beginning college students are often intensely focused on writing detailed notes. The risk is that they will miss the overall patterns and the broader significance of the topics discussed. Consider a gradual approach to the subjects of transcription and translation, beginning quite generally and testing comprehension, before venturing into the finer mechanics of each process.
• Mutations are often discussed as part of evolutionary mechanisms. In this sense, mutations may be considered a part of a creative process. The dual nature of mutations, potentially deadly yet potentially innovative, should be clarified.
Teaching Tips
• A simple way to demonstrate the effect of a reading frame shift is to have students compare the following three sentences. The first is a simple sentence. However, look what happens when a letter is added (2) or deleted (3). The reading frame is reformed into nonsense.
(1) The big red pig ate the red rag.
(2) The big res dpi gat eth ere dra g.
(3) The big rep iga tet her edr ag.
• The authors have noted elsewhere that “A random mutation is like a random shot in the dark. It is not likely to improve a genome any more than shooting a bullet through the hood of a car is likely to improve engine performance!”
Active Lecture Tips
 See the Media Review: “Learn.Genetics” Genetic Science Learning from the University of Utah on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Demonstrating a Frame Shift Mutation on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity. 25

26. 10.16 Mutations can affect genes
Mutagenesis is the production of mutations.
Mutations can be caused
by spontaneous errors that occur during DNA replication or recombination or
by mutagens, which include
high-energy radiation such as X-rays and ultraviolet light and
chemicals.
Student Misconceptions and Concerns
• Beginning college students are often intensely focused on writing detailed notes. The risk is that they will miss the overall patterns and the broader significance of the topics discussed. Consider a gradual approach to the subjects of transcription and translation, beginning quite generally and testing comprehension, before venturing into the finer mechanics of each process.
• Mutations are often discussed as part of evolutionary mechanisms. In this sense, mutations may be considered a part of a creative process. The dual nature of mutations, potentially deadly yet potentially innovative, should be clarified.
Teaching Tips
• A simple way to demonstrate the effect of a reading frame shift is to have students compare the following three sentences. The first is a simple sentence. However, look what happens when a letter is added (2) or deleted (3). The reading frame is reformed into nonsense.
(1) The big red pig ate the red rag.
(2) The big res dpi gat eth ere dra g.
(3) The big rep iga tet her edr ag.
• The authors have noted elsewhere that “A random mutation is like a random shot in the dark. It is not likely to improve a genome any more than shooting a bullet through the hood of a car is likely to improve engine performance!”
Active Lecture Tips
 See the Media Review: “Learn.Genetics” Genetic Science Learning from the University of Utah on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
 See the Activity Demonstrating a Frame Shift Mutation on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity. 26

27. Significance of Mutations
Many mutations have little or no effect on gene expression.
Some mutations are the cause of genetic disorders.
Beneficial mutations may produce proteins with new or altered activities that can be useful.
The larval skate at the bottom has had it’s gene mutated in a lab. This gene in the skate is the same gene in humans that codes for hand shape.