Name: 
 

AP Biology Chapter 17 Test



Multiple Choice
Identify the choice that best completes the statement or answers the question.
 
 
The following questions refer to Figure 17.1, a simple metabolic pathway:

nar001-1.jpg

Figure 17.1
 

 1. 

According to Beadle and Tatum's hypothesis, how many genes are necessary for this pathway?
a.
0
b.
1
c.
2
d.
3
e.
It cannot be determined from the pathway.
 

 2. 

Using RNA as a template for protein synthesis instead of translating proteins directly from the DNA is advantageous for the cell because
a.
RNA is much more stable than DNA.
b.
RNA acts as an expendable copy of the genetic material.
c.
only one mRNA molecule can be transcribed from a single gene, lowering the potential rate of gene expression.
d.
tRNA, rRNA and others are not transcribed.
e.
mRNA molecules are subject to mutation but DNA is not.
 

 3. 

A particular triplet of bases in the template strand of DNA is 5' AGT 3'. The corresponding codon for the mRNA transcribed is
a.
3' UCA 5'.
b.
3' UGA 5'.
c.
5' TCA 3'.
d.
3'ACU 5'.
e.
either UCA or TCA, depending on wobble in the first base.
 
 
The following questions refer to Figure 17.2, a table of codons.

nar002-1.jpg

Figure 17.2
 

 4. 

A possible sequence of nucleotides in the template strand of DNA that would code for the polypeptide sequence phe-leu-ile-val would be
a.
5' TTG-CTA-CAG-TAG 3'.
b.
3' AAC-GAC-GUC-AUA 5'.
c.
5' AUG-CTG-CAG-TAT 3'.
d.
3' AAA-AAT-ATA-ACA 5'.
e.
3' AAA-GAA-TAA-CAA 5'.
 

 5. 

What is the effect of a nonsense mutation in a gene?
a.
It changes an amino acid in the encoded protein.
b.
It has no effect on the amino acid sequence of the encoded protein.
c.
It introduces a premature stop codon into the mRNA.
d.
It alters the reading frame of the mRNA.
e.
It prevents introns from being excised.
 

 6. 

A frameshift mutation could result from
a.
a base insertion only.
b.
a base deletion only.
c.
a base substitution only.
d.
deletion of three consecutive bases.
e.
either an insertion or a deletion of a base.
 

 7. 

Which point mutation would be most likely to have a catastrophic effect on the functioning of a protein?
a.
a base substitution
b.
a base deletion near the start of a gene
c.
a base deletion near the end of the coding sequence, but not in the terminator codon
d.
deletion of three bases near the start of the coding sequence, but not in the initiator codon
e.
a base insertion near the end of the coding sequence, but not in the terminator codon
 

 8. 

Which of the following is not true of a codon?
a.
It consists of three nucleotides.
b.
It may code for the same amino acid as another codon.
c.
It never codes for more than one amino acid.
d.
It extends from one end of a tRNA molecule.
e.
It is the basic unit of the genetic code.
 
 
The following questions refer to Figure 17.5, a table of codons.

nar003-1.jpg

Figure 17.5
 

 9. 

Which component is not directly involved in translation?
a.
mRNA
b.
DNA
c.
tRNA
d.
ribosomes
e.
GTP
 



 
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