Biology Exam 4
17) Transcription is the ________. A) manufacture of a strand of RNA complementary to a strand of DNA B) manufacture of two new DNA double helices that are identical to an old DNA double helix C) modification of a strand of RNA prior to the manufacture of a protein D) manufacture of a protein based on information carried by RNA
A
2) DNA and RNA are polymers composed of ________ monomers. A) nucleotide B) carbohydrate C) fatty acid D) amino acid
A
24) The expressed (coding) regions of eukaryotic genes are called ________. A) caps B) promoters C) exons D) introns
C
7) In a DNA double helix, adenine pairs with ________ and guanine pairs with ________. A) cytosine... thymine B) guanine... adenine C) thymine... cytosine D) uracil... cytosine
C
8) If one strand of a DNA double helix has the sequence GTCCAT, what is the sequence of the other strand? A) ACTTGC B) TGAACG C) CAGGTA D) CAGGUA
C
29) During translation, what is the CORRECT order of events that occur as an amino acid is added? A) codon recognition, peptide bond formation, translocation B) translocation, codon recognition, termination C) initiation, codon recognition, termination D) peptide bond formation, translocation, codon recognition
A
30) Peptide bonds form between ________. A) amino acids B) an mRNA codon and a tRNA anticodon C) a tRNA and the amino acid it is carrying D) an mRNA transcript and the small ribosomal subunit
A
33) What is the smallest number of nucleotides that must be added or subtracted to change the triplet grouping of the genetic message? A) one B) two C) three D) four
A
38) Plant viruses ________. A) often use RNA, rather than DNA, as their genetic material B) benefit plants, rather than causing disease C) cause diseases that can be easily cured D) do not exist, as viruses attack only animals
A
4) Thymine and cytosine differ from adenine and guanine in that ________. A) thymine and cytosine are single-ring structures, whereas adenine and guanine are double-ring structures B) thymine and cytosine are only found in DNA, whereas adenine and guanine are found in both DNA and RNA C) thymine and cytosine are only found in DNA, whereas adenine and guanine are only found in RNA
A
41) Which of the following would NOT likely develop as an emerging virus? A) a virus harmful to humans that changes very slowly over time B) A virus that is normally harmless to humans undergoes rapid mutations. C) a virus that begins to infect people in New York City, a popular tourist destination D) a virus that affects primarily rabbits mutates and infects humans
A
43. The mutation would be most harmful to the cells if it resulted in ________. A) a single nucleotide insertion near the start of the coding sequence B) a single nucleotide deletion near the end of the coding sequence C) a single nucleotide in the middle of an intron D) deletion of a triplet near the middle of the gene
A
9) Evidence for the spiral nature of DNA came from ________. A) X-ray crystallography studies B) studies of disease-causing bacteria C) base rule studies D) bacteriophage studies
A
1) What was a surprising feature about the deadly nature of the 2009 H1N1 influenza virus? A) H1N1 affected the elderly. B) H1N1 affected healthy young people. C) H1N1 affected birds. D) H1N1 affected pigs.
B
11) After replication, ________. A) each new DNA double helix consists of two old strands B) each new DNA double helix consists of one old strand and one new strand C) each new DNA double helix consists of two new strands D) one new DNA double helix consists of two old strands and the other new DNA double helix consists of two new strands
B
14) How many amino acids are common to all living systems? A) 10 B) 20 C) 30 D) 100
B
15) How many nucleotides make up a codon? A) two B) three C) four D) five
B
20) The region of DNA where RNA synthesis begins is the ________. A) start codon B) promoter C) stop codon D) terminator
B
21) The CORRECT sequence of events occurring during transcription is ________. A) splicing, capping, tailing B) initiation, elongation, termination C) tailing, capping, splicing D) elongation, initiation, termination
B
25) Translation converts the information stored in ________ to ________. A) DNA... RNA B) RNA... a polypeptide C) DNA... a polypeptide D) RNA... DNA
B
27) The DNA codon AGT codes for an amino acid carried by a tRNA with the anticodon ________. A) TCU B) AGU C) TCA D) AGT
B
32) A mutation within a gene that will insert a premature stop codon in mRNA would ________. A) result in a longer polypeptide chain B) result in a shortened polypeptide chain C) change the location at which transcription of the next gene begins D) have the same effect as deleting a single nucleotide in the gene
B
40) HIV (human immunodeficiency virus) must use its own ________ to reproduce. A) DNA polymerase B) reverse transcriptase C) RNA polymerase D) tRNA
B
42. The mutation that resulted from the accident was probably ________. A) an amino acid substitution B) one that changed the triplet grouping of the genetic message C) an error in translation D) a loss in regulation of gene expression
B
5) RNA contains the nitrogenous base ________ instead of ________, which is found only in DNA. A) a deoxyribose sugar... a ribose sugar B) uracil... thymine C) uracil... guanine D) thymine... uracil
B
13) What name is given to the collection of traits exhibited by an organism? A) genome B) genotype C) phenotype D) genetic code
C
16) The shared genetic code of all life on Earth is evidence that ________. A) the genetic code arose relatively late in the history of life on Earth B) DNA replication is error-free C) all life shares a common ancestry D) bacterial cells arose earlier than eukaryotic cells
C
18) If a strand of DNA has the sequence AAGCTC, transcription will result in a(n) ________. A) single RNA strand with the sequence TTCGAG B) DNA double helix with the sequence AAGCTC for one strand and TTCGAG for the complementary strand C) single RNA strand with the sequence UUCGAG D) RNA double helix with the sequence UUCGAG for one strand and AAGCUC for the complimentary strand
C
22) The absence of a terminator in transcription will result in ________. A) the creation of a virus B) a strand of mRNA that lacks its cap and tail C) the production of a longer RNA molecule D) the production of a shorter RNA molecule
C
28) Where is translation accomplished? A) lysosomes B) smooth endoplasmic reticulum C) ribosomes D) nucleoli
C
3) The backbone of DNA consists of ________. A) nitrogenous bases B) a repeating sugar-nucleotide-sugar-nucleotide pattern C) a repeating sugar-phosphate-sugar-phosphate pattern D) paired nucleotides
C
31) Scientific research companies sell kits that allow researchers to produce proteins in test tubes via a process known as "in vitro translation." Which one of following components is NOT needed in these kits? A) amino acids B) transfer RNA C) DNA D) ribosomes
C
36) How can bacteriophage DNA be spread from cell to cell without causing cell death? A) by altering the way a cell splices its RNA B) via a lytic cycle C) via a lysogenic cycle D) by changing the length of its DNA molecules
C
37) As an experiment, you infect bacteria with an unknown virus to see how the bacteriophage affects the bacteria. After a few days, you notice that the bacterial population is growing normally and that the cells appear healthy. Assuming that the infection occurred, what can you conclude from your observations? A) The virus is a bacteriophage that is reproducing the lytic cycle. B) The virus is a retrovirus that is reproducing the lytic cycle. C) The virus is a bacteriophage that is reproducing the lysogenic cycle. D) The virus is a retrovirus that is reproducing the lysogenic cycle.
C
39) A(n) ________ is to bacteria as a ________ is to animal cells. A) retrovirus... virus B) phage... prophage C) prophage... provirus D) RNA virus... DNA virus
C
10) What type of chemical bond joins the bases of complementary DNA strands? A) ionic B) covalent C) hydrophilic D) hydrogen
D
12) DNA replication ________. A) is a slow process that results in virtually no errors B) requires DNA polymerase and RNA polymerase C) is a very fast process that results in numerous errors D) requires the cooperation of over a dozen enzymes and other proteins
D
19) Which of the following enzymes is responsible for RNA synthesis? A) DNA polymerase B) ribosome C) reverse transcriptase D) RNA polymerase
D
23) What protects mRNA from attack by cellular enzymes? A) RNA splicing B) the removal of exons C) the lack of RNA-digesting enzymes in the cytoplasm D) a cap and tail
D
26) The RNA that is translated into a polypeptide is ________ RNA. A) viral B) ribosomal C) transfer D) messenger
D
34) What is the ultimate source of all diversity? A) natural selection B) sexual recombination C) meiosis D) mutation
D
35) Mad cow disease is caused by A) a retrovirus similar to HIV. B) an enveloped virus. C) small circular RNA molecules called viroids. D) infectious proteins called prions.
D
6) If adenine makes up 20% of the bases in a DNA double helix, what percent of the bases is guanine? A) 60% B) 40% C) 20% D) 30%
D
