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Bio 9B: Monday, 2.28.11
Title: RNA Structure and Function

Homework:

Read pages 300-302 in the textbook. Take active reading notes to answer the
following questions:




How is RNA different from DNA?
What are the functions of the 3 different types of RNA?
What happens during transcription?
Do Now: In your notebook:

If you had a DNA sequence of T A C A G C T, what would the matching
RNA sequence be?
AUGUCGA

Today’s Objectives:


Describe the major structural differences between DNA and RNA
Differentiate between structure and function differences between the types of
RNA
RNA:
STRUCTURES & FUNCTIONS
PHA Biology 9
Moretti and Dickson
RNA Structure & Function of Different Types
RNA Structure: Base Pairing

4 Nitrogen Bases in RNA:
 Adenine
 Guanine
 Uracil
 Cytosine

RNA –> DNA Base Pairing:
A ---- U
G ---- C
Objectives for Class:
• Describe the major structural differences between DNA and RNA
• Differentiate between structure and function differences between the types of RNA
RNA Structure: DNA vs. RNA
3 Major Structural Differences
DNA
RNA
Deoxyribose Sugar
Ribose Sugar
Double Strand
Single Strand
(generally)
Uses Thymine (T)
Uses Uracil (U)
Objectives for Class:
• Describe the major structural differences between DNA and RNA
• Differentiate between structure and function differences between the types of RNA
Types of RNA: Overview
Type of RNA
Basic Function
Messenger RNA (mRNA) Copy genes on the DNA
(transcription)
Transfer RNA (tRNA)
Translate mRNA into a protein
Carry amino acid to the ribosome
Ribosomal RNA (rRNA)
Part of the ribosome
(we will not focus on rRNA)
Objectives for Class:
• Describe the major structural differences between DNA and RNA
• Differentiate between structure and function differences between the types of RNA
Types of RNA: Messenger RNA (mRNA)

Basic Structure:


Single Strand of RNA
Basic Function
Make a copy of DNA instructions to
make a protein
 Takes those instructions from DNA to
Ribosome to make a protein
 Every 3 bases is a Codon

Remember: Small enough to leave
the nucleus. DNA is too big!
Objectives for Class:
• Describe the major structural differences between DNA and RNA
• Differentiate between structure and function differences between the types of RNA
Types of RNA: Transfer RNA (tRNA)

Basic Structure:




Coiled RNA strand
Amino Acid attached to the top
Anti-codon on the bottom
Basic Function:

Transfer amino acids to the
ribosome to make a protein

Anti-codon on tRNA matches/
reads codon on mRNA
Objectives for Class:
• Describe the major structural differences between DNA and RNA
• Differentiate between structure and function differences between the types of RNA
Types of RNA: Transfer RNA (tRNA)
Objectives for Class:
• Describe the major structural differences between DNA and RNA
• Differentiate between structure and function differences between the types of RNA
RNA Structure & Function HW Work Time
Bio 9B: Tuesday, 2.28.11
Title: RNA Structure and Function

Homework:


Do Now: In your notebook:


Read pages 302-306 in the textbook. Take active reading notes,
paying attention to important vocabulary terms and to the following
purpose questions:
 How does the genetic code work?
 What are the steps of translation?
Next Slide
Today’s Objectives:
Explain the purpose of transcription and translation
 Describe the steps of translation
 Use the genetic code to translate a gene into a protein

MCAS Prep Question
The mold Aspergillus flavus grows on grain. A. flavus
produces a toxin that binds to DNA in the bodies of animals
that eat the grain. The binding of the toxin to DNA blocks
transcription, so it directly interferes with the ability of an
animal cell to do which of the following?
A.
B.
C.
D.
Produce ATP using energy released from glucose and other
nutrient
transport glucose across the cell membrane into the cytoplasm
Transfer proteins from the endoplasmic reticulum to Golgi
complexes
Send protein-building instructions from the nucleus to the
cytoplasm and ribosomes
The Genetic Code

The 64 Codons that code for Amino Acids
Objectives for Class:
• Use the genetic code to translate a DNA or RNA sequence into an amino acid sequence to make a protein.
Reading The Genetic Code




mRNA codons are 3 bases long
and specify a particular amino
acid.
To use the wheel, the 1st base
(letter) of codon matches the
biggest letter and you move
out from the middle to read
the rest of the codon.
Therefore, the 2nd base in
the codon is the second
biggest letter (the one in the
middle ring) and the 3rd base
In the codon is the smallest
letter (the one in the outer ring).
The arrows show the direction
you should read it.
The Genetic Code

Complete Part I of the
“Decoding the Genetic
Code!” Activity.
(we will review the first 3
examples of question 1 after you
have had a chance to complete
them)
Objectives for Class:
• Use the genetic code to translate a DNA or RNA sequence into an amino acid sequence to make a protein.
Reading The Genetic Code: Examples
Follow along with the
examples in your packet!
Example 1: CAG



1st base = C
2nd base = A
3rd base = G
Therefore the
amino acid is…
 Glutamine!
Example 2: GUU
 Valine
Reading The Genetic Code: Longer Example
Example 3:
GCCAGCUAG
Step 1: Break it
into 3-letter
sections (codons)
GCC AGC UAG





Step 2: Decode 2
each codon
GCC = Alanine
AGC = Serine
UAG = STOP (end
of protein sequence)
1
3
Homework Review Question

Overview:
 What
is the hidden message in Part II of the
homework assignment?
 “Give Neighbor High 5”
Objectives for Class:
•Describe the purpose and major steps of transcription
•Describe the purpose and major steps of translation
Transcription Detail

Overview:



A DNA gene is copied in the
form of mRNA
Occurs in the nucleus
Steps:
1.
2.
3.
RNA Polymerase separates
DNA strands
RNA Polymerase moves along
one of the DNA strands
(template)
RNA Polymerase makes mRNA
by attaching RNA nucleotides
that match the DNA template
Objectives for Class:
•Describe the purpose and major steps of transcription
•Describe the purpose and major steps of translation
mRNA
Types of RNA: Messenger RNA (mRNA)
DNA
(the red &
green strands)
mRNA
(the orange strand)
Objectives for Class:
• Describe the major structural differences between DNA and RNA
• Differentiate between structure and function differences between the types of RNA
Translation Detail

Overview:



mRNA copy provides instructions for
assembling amino acids into a protein
Occurs at the ribosome
Steps:
1. mRNA enters the ribosome
2. tRNA molecules bring amino acids
to the ribosome
3. tRNA anticodons match with mRNA
codons to put amino acids in the
right order

According to the Genetic Code
Objectives for Class:
•Describe the purpose and major steps of transcription
•Describe the purpose and major steps of translation
Transcription & Translation
Transcription
Objectives for Class:
•Describe the purpose and major steps of transcription
•Describe the purpose and major steps of translation
Translation
Translation
Objectives for Class:
•Describe the purpose and major steps of transcription
•Describe the purpose and major steps of translation
Transcription and Translation: Video

Transcription and Translation Video:
17_13ProteinSynthesis.mpg
Objectives for Class:
•Describe the purpose and major steps of transcription
•Describe the purpose and major steps of translation
Bio 9B: Wednesday, 3.2.11
Title: Genetic Mutations Day 1 – Types of Mutations

Homework:
Complete Part II of the Genetic Mutations Activity For Tomorrow
 Quiz next TUESDAY!


Do Now:
 How
was your description of a genetic mutation similar to
what a mutation actually is?

Today’s Objective:
 Describe
the major differences between substitution and
frame-shift mutations
Gene Mutations Activity Part I Review

What is a Genetic Mutation?
A

change in the base-pair sequence of DNA
The three types of point mutations:
 substitution
(switch one DNA nucleotide for another)
 insertion (add an extra nucleotide into the DNA
sequence)
 deletion (leave out one nucleotide in the DNA sequence)
Objectives for Class:
•Describe the major differences between substitution and frame-shift mutations
Gene Mutations Activity Part II


Complete Part II of the Gene Mutations Activity by comparing substitution &
frame-shift mutations
Part II Review:

Original DNA Sequence
Objectives for Class:
•Describe the major differences between substitution and frame-shift mutations
Gene Mutations Activity Part II

Substitution Mutations
 Original DNA Sequence

Substitution
Changes the
Amino Acid

Substitution/ Silent Mutation
Does not
Change the
Amino Acid
Objectives for Class:
•Describe the major differences between substitution and frame-shift mutations
Gene Mutations Activity Part II

Frame-Shift Mutations
 Original DNA Sequence

Frame-Shift: Deletion of nucleotide
Changes all
Amino Acid
after mutation

Frame-Shift: Insertion/ Addition of nucleotide
Changes all
Amino Acid
after mutation
Objectives for Class:
•Describe the major differences between substitution and frame-shift mutations
Bio 9B: Thursday, 3.3.11
Title: Transcribe and Translate a Gene Computer Lab

Homework:
Double Block
Pass in the codons and amino acid decoding practice homework
 Complete Part II of the Computer Lab


Do Now:
 Which
type of genetic mutation (deletion, substitution, or
insertion) seems to have the biggest impact on a gene and
why?.

Today’s Objective:
 Use
the steps of transcription and translation to turn a section
of DNA into a protein.
Reviewing Genetic Mutations
Gene Mutations Activity Part II

Substitution Mutations
 Original DNA Sequence

Substitution
Changes the
Amino Acid

Substitution/ Silent Mutation
Does not
Change the
Amino Acid
Objectives for Class:
•Describe the major differences between substitution and frame-shift mutations
Gene Mutations Activity Part II

Frame-Shift Mutations
 Original DNA Sequence

Frame-Shift: Deletion of nucleotide
Changes all
Amino Acid
after mutation

Frame-Shift: Insertion/ Addition of nucleotide
Changes all
Amino Acid
after mutation
Objectives for Class:
•Describe the major differences between substitution and frame-shift mutations
Protein Synthesis Computer Lab
Transcribe and Translate a Gene Computer Lab
Procedure:







Log onto http://gslc.genetics.utah.edu/units/basics/transcribe/
Scroll down to the middle of the homepage and click on the link
entitled “Are you ready to transcribe a DNA sequence and
translate it into a protein?”
A DNA sequence should appear on the screen. Transcribe the
DNA strand by entering the corresponding RNA bases for the
original strand. The new mRNA strand will now appear on the
screen.
Locate the “start” codon and click on it with your mouse. The
mRNA sequence will now move to the top of the field and a
flashing box will appear around the “start” codon.
Using the “Universal Genetic Code” to the right, find the amino
acid that corresponds with the three-base mRNA codon. Click on
the appropriate amino acid and drag it to the corresponding
mRNA codon (signaled by the flashing box). Repeat until the
mRNA sequence has been Translated.
Answer the Review and Analysis questions for Part I as you
complete the lab.
Answer the Review and Analysis questions for Part II after the
computer portion of the lab is completed.
Transcription
Objectives for Class:
• Use the steps of transcription and translation to turn a section of DNA into a protein.
Translation
Remember R-groups?
Complete Part II of the Lab

Be sure Part II is completed on a separate sheet of
paper!
Bio 9B: Monday, 3.8.10
Title: Genetic Mutations Day 2 – Sickle Cell Case Study

Homework:



Do Now:


Study for Quiz Tomorrow!!!
Type the Background Information section of your lab report for Thursday.
(NOTE: completed lab reports are due Friday at the start of class. You will
have time to work on it during Thursday’s class, but if you need more time/
don’t have access to a computer at home, please make arrangements now to
complete the lab Thursday after school)
Which of the different mutations has the biggest effect on the amino
acid sequence? What effect does this have on the protein? What
would happen to an enzyme that experienced this type of mutation?
Today’s Objective:

Brainstorm and organize the background information necessary to
successfully explain what sickle cell anemia is and how it is caused.
Gene Mutations Activity Part II

Frame-Shift Mutations
 Original DNA Sequence

Frame-Shift: Deletion of nucleotide
Changes all
Amino Acid
after mutation

Frame-Shift: Insertion/ Addition of nucleotide
Changes all
Amino Acid
after mutation
Objectives for Class:
•Describe the major differences between substitution and frame-shift mutations
Lab: Sickle Cell and Genetic Mutations
A Case Study of Sickle Cell Disorder
 Read through the Introduction to the lab.
 Watch 5 minute video on sickle cell disorder

PBS Evolution Library: A Mutation Story


http://www.pbs.org/wgbh/evolution/library/01/2/l_012_02.html
In small groups brainstorm the Background Information
needed for this lab

You should have 2 parts:
1.
2.

General genetics background info
Info related to sickle cell anemia
Come back together as a class to brainstorm final list
Objectives for Class:
• Brainstorm and organize the background information necessary to successfully explain what sickle cell anemia is and
how it is caused.
Bio 9B: Tuesday, 3.9.10
Title: Quiz – Transcription, Translation, and Mutations

Homework:


Do Now:


Type the Background Information section of your lab report for
Thursday. (NOTE: completed lab reports are due Friday at the start
of class. You will have time to work on it during Thursday’s class, but
if you need more time/ don’t have access to a computer at home,
please make arrangements now to complete the lab Thursday after
school)
Clear your desks and get ready to take the quiz…
Today’s Objective:

Demonstrate your understanding of how the processes of
transcription and translation create proteins from the genetic
code on DNA
Bio 9B: Thursday, 3.11.10
Title: Genetic Mutations Day 3 – Sickle Cell Case Study

Homework:


Do Now:


Complete the Procedure, Analysis and Conclusion sections of your lab
report. Completed lab report with all sections is due tomorrow, Friday,
at the start of class!!!!
Whole Class – Brainstorm Background Information Section.
Today’s Objective:
Analyze the DNA sequence for the sickle cell gene and the
normal gene to determine how DNA is mutated to result in sickle
cell anemia
 Complete the Sickle Cell Mutation Lab Report

Lab: Sickle Cell and Genetic Mutations
Background Information Brainstorm
Genetics Topics:
• Genes- what they do and how they make traits
•DNA-molecule that carries genetic info
•Chromosomes-DNA makes up chromosomes [optional]
•Nucleotides-the pattern of them
•Proteins-how they are made from genetic codes
•Transcription and Translation
•How are proteins made? [amino acids]
•The sequence of amino acids
•Amino acids make up the structure of the protein. The structure of the protein determines the function.
•Vocabulary- Codon’s etc.
•Gene Expressions [optional]
•Mutations [briefly describe3 different types]
Sickle Cell Topics:
• Definition: genetic disorder-hereditary –mutates the hemoglobin protein in red blood cells, which carries
oxygen to the body.
•Definition of hemoglobin
•The impact of sickle cell on the body.
First Half of Double Block
Lab: Sickle Cell and Genetic Mutations
A Case Study of Sickle Cell Disorder…
 Write the purpose of the lab
 Develop your hypothesis based on the purpose
 Analyze the DNA sequence for the sickle cell gene and the
normal gene by transcribing and translating them.
 Compare the sickle cell gene to the normal gene
 Complete the analysis and conclusion sections of the lab
report.
http://www.pbs.org/wgbh/evolution/library/01/2/l_012_02.html
Objectives for Class:
• Analyze the DNA sequence for the sickle cell gene and the normal gene to determine how DNA is mutated to result
in sickle cell anemia
Second Half of Double Block
Lab: Sickle Cell and Genetic Mutations
Individual Work Time…

Two Options:
1.
Type Analysis and Conclusion sections of lab report and
revise your other sections
2.
Guided peer review of Background Information section
Objectives for Class:
• Analyze the DNA sequence for the sickle cell gene and the normal gene to determine how DNA is mutated to result
in sickle cell anemia
• Complete the Sickle Cell Mutation Lab Report
Bio 9B: Friday, 3.12.10
Title: Sickle Cell Case Study – Lab Report Peer Review

Homework:
Complete the Sickle Cell lab report revision for Monday.
 Complete the Bio-Blog homework for Tuesday (Meiosis Vocab):

http://phascience.wordpress.com/biology-9-moretti-dickson-powerpoint-notes-etc/

Do Now:


Divide class into peer editing teams.
Today’s Objective:
 Peer
review and complete the Sickle Cell Mutation Lab
Report