Supplemental Instruction
Iowa State University
Leader: Lilli Howard
Course: BIOL/GEN 313
Instructor: Dr. Rodermel/Dr. Tuggle
Date: 10/20/14
1.
The genetic code has ____ letters which are: ___________________________.
2.
The genetic code is a ___________ code. Meaning each __________ ________ is encoded by ____ nucleotides. a.
Describe the in vitro translation of nucleotides experiment. What was the conclusion from this experiment? b.
Describe the ribosome-bound tRNA experiment. What was the conclusion from this experiment?
3.
The codon table is comprised of ____ codons and is read 5’  3’ in the ________. a.
Using this table, what are the possible codons for serine? b.
Using this table, what does the codon CAU code for?
4.
5.
The genetic code is degenerate. Describe what that means.
Match the following terms to their definitions: a.
b.
c.
Sense codon(s) _______
Termination codon(s) _______
Initiation codon(s) _______
1.
signal end of the protein
2.
specify amino acids
3.
do not encode an amino acid
4.
codon that specifies Met
5.
61 different codons
6.
1 codon
7.
3 different codons
6.
________________________ are codons that specify the same amino acid.
7.
Because any given nucleotide is only included in one codon, we say that the genetic code is __________________________. a.
What is a reading frame? How many different reading frames are there?
8.
The ________________ _________ sets the reading frame.
9.
Crick’s proposal of an adaptor molecule included two requirements:
1.
______________________________________
2.
______________________________________ a.
What is the adapter molecule known as now? Describe it. How many are there?
10.
What does the Wobble Hypothesis predict? a.
Think of an example of an anticodon. Would wobble apply in that case?
11.
The code is _________________, which means that each codon specifies the same amino acid in all organisms. (There are very few exceptions)
1060 Hixson-Lied Student Success Center  515-294-6624  sistaff@iastate.edu  http://www.si.iastate.edu

Concept Checks
1.
Through wobble, a single ___________ can pair with more than one _________. a.
Codon, anticodon b.
Group of 3 nucleotides in DNA, codon in mRNA c.
tRNA, amino acid d.
anticodon, codon
2.
Do the initiation and termination codons specify an amino acid? If so, which ones?
3.
Amino acids bind to which part of the tRNA? a.
Anticodon b.
DHU arm c.
3’ end d.
5’ end
4.
What are isoaccepting tRNAs?
5.
A series of tRNAs have the following anticodons. Consider the wobble rules and give all possible codons with which each tRNA can pair. a.
5’- GGC -3’ b.
5’- AAG -3’ c.
5’- IAA -3’ d.
5’- UGG -3’ e.
5’- CAG -3’
6.
An anticodon on a tRNA has the sequence 5’ – GCA - 3’ a.
What amino acid is carried by this tRNA? b.
What would be the effect if the G in the anticodon were mutated to U?
1060 Hixson-Lied Student Success Center  515-294-6624  sistaff@iastate.edu  http://www.si.iastate.edu

1060 Hixson-Lied Student Success Center  515-294-6624  sistaff@iastate.edu  http://www.si.iastate.edu