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Question
____ 
-sheets characteristically distribute hydrophobic side chains on both sides of the sheet, and
____-sheets are usually arranged with all their hydrophobic residues on one side of the sheet.
a. Antiparallel, parallel
b. Antiparallel, antiparallel
c. Parallel, antiparallel
d. Parallel, parallel
e. None of the above
Answer
This answer is hidden. It contains 1 characters.
Related questions
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In general, proteins whose folding is chaperone-dependent start the folding process first with ____ and then are passed as ____ folded intermediates to ____.
a. Hsp40; un-; Hsp70
b. Hsp90; un-; chaperonin
c. Hsp70; partially; chaperonin
d. Hsp40; partially; Hsp70
e. Hsp60; partially; Hsp40
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Which of the following is responsible for Alzheimer's disease?
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b. neurofibrillary tangles of polymeric microtubule-binding protein tau
c. extracellular deposits of amyloid-ï¢ and intracellular neurofibrillary tangles of microtubule-binding protein tau
d. mutation in the huntingtin gene
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Which of the following correctly describes the order of events in the class I aminoacyl-tRNA synthetase reaction?I. displacement of AMPII. transesterificationIII. nucleophilic attack by 2'-hydroxyl of the tRNA on the acyl adenylateIV. formation of acyl adenylate by reaction of amino acid with ATPV. displacement and subsequent hydrolysis of pyrophosphatea. III, I, IV, V, IIb. III, V, IV, I, IIc. IV, II, I, III, Vd. IV, V, III, I, IIe. IV, I, III, II, V
Q:
In a class I aminoacyl-tRNA synthetase, which of the following reacts with the acyl phosphate formed during the reaction of ATP with the amino acid?a. 5'-hydroxyl of the nucleotide on the 5' end of the tRNA moleculeb. 3'-hydroxyl of the nucleotide on the 5' end of the tRNA moleculec. 2'-hydroxyl of the nucleotide on the 5' end of the tRNA moleculed. 3'-hydroxyl of the nucleotide on the 3' end of the tRNA moleculee. 2'-hydroxyl of the nucleotide on the 3' end of the tRNA molecule
Q:
Each of the following statements regarding ways in which eukaryotic protein synthesis differs from prokaryotic protein synthesis is true EXCEPT:
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b. prokaryotes use a 30S small ribosomal subunit, while eukaryotes use a 40S small ribosomal subunit
c. prokaryotic and eukaryotic translation initiation differ significantly in mechanism and process
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e. all of the above are true statements
Q:
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Q:
Termination of translation in prokaryotic cells requires:
a. binding of the terminator tRNA to the termination codon.
b. interaction of release factors with the termination codon.
c. ternary interaction of the release factor and the termination tRNA with the termination codon.
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Q:
Which of the following does not reqire GTP hydrolysis?
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b. the binding of the aminoacyl tRNA to the A site during elongation
c. translocation with release of the uncharged tRNA during elongation
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Q:
Which of the following statements is true regarding the formylmethionine that serves as the first amino acid in bacterial protein synthesis?
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Q:
Mitochondrial and chloroplastic ribosomes resemble ____ ribosomes.
a. prokaryotic
b. lower eukaryotic
c. higher eukaryotic
d. no other
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Q:
Ribosomal proteins are typically rich in the amino acids ____ and ____ to interact with ____ RNAs.
a. asp; glu; polycationic
b. asp; ala; polycationic
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Q:
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Q:
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Q:
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Q:
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d. The code is universally used by virtually all species.
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Q:
The linkage between the amino acid and the tRNA in an amino-acyl tRNA complex is:
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Q:
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Q:
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Q:
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Q:
The base-pair edges in the ____ groove act as a(n) ____ identifiable through ____ with specific proteins.
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Q:
The eukaryotic transcription factor that exhibits a sequence specificity for the TATA box is:
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b. TFIIC.
c. TFIID/TBP.
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Q:
All are correct about enhancer sequences in eukaryotic cells EXCEPT:
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Q:
All are characteristics of catabolic activator protein (CAP) EXCEPT:
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b. overrides the influence of any inducer that might be present.
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e. all are true.
Q:
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Q:
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Q:
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b. a base analog such as 5-bromouracil
c. a chemical mutagen such as nitrous acid
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Q:
Which of the following statements explains why the adenine analog, 2-aminopurine (2-AP), can cause mutations in DNA when it is inserted in place of a site normally occupied by A?
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e. none of the above
Q:
Misincorporation of all subsequent amino acids results from ____ mutations.
a. chemical
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Q:
Mutations in DNA may result from all of the following EXCEPT:
a. spontaneous mutations due to errors in replication.
b. physical insults on the cell, such as UV light.
c. errors in transcription.
d. chemical mutagens.
e. introduction of a base analog into DNA.
Q:
A transition mutation would be replacing A by:
a. T.
b. C.
c. U.
d. G.
e. either T or C