CHAPTER 15, GENE ACTIVITY. HOW GENES WORK

_____1. The concept of an "inborn error of metabolism" was the first recognition of the relationship between
gene activity and metabolic disease, made by
a) Beadle and Tatum with parasitic molds.
b) Pauling and Itano with sickle cell anemia.
c) Sir Archibold Garrod from general family inheritance patterns.
d) Watson and Crick, as a natural outcome of their model of DNA.
e) Gregor Mendel, who extrapolated his pea plant data to human disease.

_____2. Studies by Beadle and Tatum that produced the "one gene-one enzyme hypothesis"
were conducted using the
a) bread mold Neurospora crassa
b) bacterium Streptococcus pneumoniae
c) bacterium E. coli
d) mouse
e) human

_____3. The idea that a single gene coded a polypeptide rather than an enzyme was evident from the
a) use of X-rays to make nutritional mutants in bread mold.
b) transformation of bacteria from rough and nonvirulent to smooth and virulent.
c) presence of a mutation in one chain of hemoglobin but not in the other.
d) discovery that mutated genes changed enzymes in a biochemical pathway.
e) finding that some genes in eukaryotes are split by introns.

_____4. Today, it is most appropriate to state that a gene controls
a) one enzyme
b) one protein
c) one polypeptide chain
d) one amino acid
e) one starch, amino acid or lipid molecule

_____5. Which of the following classes of RNA molecules carries the genetic information as it is needed
for the construction of a protein?
a) ribosomal RNA b) transfer RNA c) messenger RNA d) primary mRNA transcript

_____6. Which of the following classes of RNA molecules carries the amino acids that are added to the
growing polypeptide chain?
a) ribosomal RNA b) transfer RNA c) messenger RNA d) primary mRNA transcript

_____7. Which of the following classes of RNA molecules is found in almost no prokaryotes?
a) ribosomal RNA b) transfer RNA c) messenger RNA d) primary mRNA transcript

_____8. Which of the following classes of RNA molecules is linked with proteins in forming the large and
small subunits of a cytoplasmic structure?
a) ribosomal RNA b) transfer RNA c) messenger RNA d) primary mRNA transcript

_____9. Prior to protein synthesis, the DNA
a) attracts tRNAs with appropriate amino acids.
b) must first undergo replication.
c) contains anticodons that must become codons.
d) serves as a template for the production of mRNA.
e) adheres to ribosomes for protein synthesis.

_____10. Which of the following classes of RNA molecules is never found in the cytosol?
a) ribosomal RNA b) transfer RNA c) messenger RNA d) primary mRNA transcript

_____11. The first codon to be deciphered was _______, which codes for ______.
a) AAA, praline b) GGG, alanine c) UUU, phenylalanine d) TTT, arginine e) CCC, glycine

_____12. Transcription of a part of a DNA molecule with a nucleotide sequence of A-A-A-C-A-A-C-T-T
results in a mRNA molecule with the complementary sequence of
a) G-G-G-A-G-A-A-C-C
b) U-U-U-G-U-U-G-A-A
c) T-T-T-G-A-A-G-C-C
d) C-C-C-A-C-C-T-C-C
e) None of the above.

_____13. If one strand of DNA has the base sequence A-A-G-C-A-A, the complementary strand
has which of the following sequences?
a) U-U-C-G-U-U b) T-T-C-G-T-T c) A-A-G-C-A-A d) U-T-C-G-T-U e) T-T-C-G-T-G

_____14. Which is the process that synthesizes mRNA, tRNA, or rRNA?
a) translation b) transcription c) transposition d) transformation

_____15. Which of the following nucleotide bases is found only in RNA, not in DNA?
a) guanine b) adenine c) thymine d) uracil e) cytosine

_____16. Which of the following nucleotide bases is found only in DNA, not in RNA?
a) guanine b) adenine c) thymine d) uracil e) cytosine

_____17. An intervening sequence in a eukaryotic gene that is not an active part of the gene is called a(n)
a) exon b) intron c) replicon

_____18. A ribozyme is
a) a section of the DNA that is expressed in the mRNA.
b) a self splicing intron that acts like an enzyme.
c) a complex made up of many ribosomes replicating the same strand of mRNA.
d) one of the small ribosomal subunits.
e) the enzyme that attaches amino acids to tRNA.

_____19. Which is the process by which a protein is constructed?
a) translation b) transcription c) transposition d) transformation

_____20. In order to produce many copies of a protein fast, the cell uses
a) DNA replication
b) intron self splicing
c) codon-anticodon reciprocal duplication
d) many RNA polymerase molecules to produce mRNA transcripts at the same time

_____21. Which is most directly responsible for the sequence of amino acids in a protein?
a) the sequence of the anticodons
b) the number of codons in mRNA
c) the enzyme that attaches the amino acid to tRNA
d) the proteins associated with rRNA
e) the sequence of codons in mRNA

_____22. Which is Not true about the genetic code?
a) It is exactly the same in all organisms.
b) It is composed of triplet code of three bases per codon.
c) It produces 64 different possibilities of base sequences.
d) It was cracked through the use of a cell free system of enzymes.

_____23. For translation to take place, which of the following would Not be required to be present?
a) DNA b) mRNA c) RNA-amino acid complex d) rRNA e) ribosome

_____24. Which of the following processes does Not take place during translation?
a) Growth of a polypeptide chain.
b) Attachment of a ribosome to mRNA.
c) Binding of two tRNA molecules per ribosome.
d) Liberation of polypeptide from ribosome.
e) Production of mRNA.

_____25. The correct sequence of events in the production of a polypeptide is
a) initiation, termination, elongation
b) elongation, termination, initiation
c) termination, elongation, initiation
d) elongation, initiation, termination
e) initiation, elongation, termination

_____26. Which of the following is Not a form of ribonucleic acid, or RNA?
a) messenger RNA b) ribosomal RNA c) transfer RNA e) translation RNA

_____27. During transcription, the genetic information is rewritten as a molecule of
a) messenger RNA b) ribosomal RNA c) transfer RNA e) translation RNA

_____28. In a cell, the equipment for translation is located in the
a) cytosol b) nucleus c) plasma membrane d) centrioles

_____29. The number of nucleotides required to specify one amino acid is called a
a) genome b) codon c) radon d) intron e) exon

_____30. Each codon is how many nucleotides long?
a) 3 b) 4 c) 5 d) 6 e) 9

_____31. Each codon specifies a(n)
a) genetic sequence b) amino acid c) nucleotide d) intron e) exon

_____32. Codon that signal the end of a polypeptide chain are called
a) silent codons b) secret codons c) stop codons d) stop introns

_____33. How many amino acids are there?
a) 8 b) 9 c) 10 d) 20 e) 64

_____34. The process by which DNA transfers its information to RNA is called
a) transmutation b) transmittal c) translation d) transcription

_____35. During transcription, the information in the DNA is rewritten, or transcribed, in the form of
a) RNA b) proteins c) codons d) polypeptides

_____36. The RNA copy of the information from DNA is composed of
a) tRNA b) mRNA c) pRNA d) rRNA

_____37. The conversion of the message carried by the RNA into polypeptides is called
a) transmutation b) transmittal c) translation d) transcription

_____38. The starting signal for mRNA synthesis is a special sequence of DNA called a
a) promoter b) director c) polymerase d) primer

_____39. In eukaryotes transcription factors lead the RNA polymerase to the
a) adjacent polypeptide b) promoter c) codon d) primer

_____40. Both eukaryotes and prokaryotic RNA polymerase stop transcription at a special sequence called
a) transcriptors b) terminal codons c) terminators d) translation ends

_____41. Interruptions in pre-mRNA, or intervening sequences, are called
a) positrons b) interrupters c) introns d) mistakes

_____42. In RNA, thymine is replaced by
a) adenine b) guanine c) cytosine d) uracil