Biochemistry, The Molecular Basis of Life, 6th Edition
6th Edition
ISBN: 9780190259204
Author: Trudy McKee, James R. McKee
Publisher: Oxford University Press
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Chapter 19, Problem 63TQ
Summary Introduction
To review:
The way in which errors made by aminoacyl-transfer ribonucleic acid (tRNA) synthetases are detected and corrected.
Introduction:
The aminoacyl tRNA synthetases are a versatile group of enzymes. These have a lot of variations in molecular weight, primary sequence, and thenumber of subunits. The specificity with which tRNAsynthetase produces correct aminoacyl-tRNA is the basis of translation. Sometimes, these enzymes produce errors due to the similarstructure of some amino acids.
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Given the values for the changes in enthalpy (AH) and entropy (AS), which processes can take place at 298 K without
violating the Second Law of Thermodynamics?
(a) AH =
(b) AH = -84 kJ mol¹ (−20 kcal mol¹), AS = -125 J mol-¹ K-¹ (-30 cal mol-¹ K-¹)
(c) AH = +84 kJ mol¹ (+20 kcal mol¯¹), AS = +125 J mol¯¹ K−¹ (+30 cal mol-¹ K-¹)
(d) AH = +84 kJ mol-1 (+20 kcal mol-¹), AS = -125 J mol¯¹ K-¹ (-30 cal mol-¹ K-¹)
-84 kJ mol¹ (-20 kcal mol¹), AS = +125 J mol¯¹ K-¹ (+30 cal mol-¹ K-¹)
What chemical interactions are primarily responsible for the fact that oil and water do not mix easily?
ionic interactions
covalent bonds
hydrogen bonding
Ohydrophobic effect
The carbon-nitrogen peptide bond is rigid, but rotation can take place
about the bond between the nitrogen and α-carbon atoms and the bond
between the α-carbon and the carbonyl carbon atom. These bond angles
define the conformation of the peptide chain.
Consider the Ramachandran plot shown to answer both questions.
(degrees)
180
120
60
60
0
Which observation most likely describes part of an observed a helix?
p=-59 degrees; = +150 degrees; many Ser residues
cp-140 degrees; w = +130 degrees; many Val residues
op-57 degrees; w = -47 degrees; many Pro residues
op-60 degrees; y = -47 degrees; many Ala residues
p = +60 degrees; y = +40 degrees; many Gly residues
-60
-120
-180
-180
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➜ (degrees)
180
Chapter 19 Solutions
Biochemistry, The Molecular Basis of Life, 6th Edition
Ch. 19 - Prob. 1QCh. 19 - Prob. 2QCh. 19 - Prob. 3QCh. 19 - Prob. 4QCh. 19 - Prob. 5QCh. 19 - Prob. 1RQCh. 19 - Prob. 2RQCh. 19 - Prob. 3RQCh. 19 - Prob. 4RQCh. 19 - Prob. 5RQ
Ch. 19 - Prob. 6RQCh. 19 - Prob. 7RQCh. 19 - Prob. 8RQCh. 19 - Prob. 9RQCh. 19 - Prob. 10RQCh. 19 - Prob. 11RQCh. 19 - Prob. 12RQCh. 19 - Prob. 13RQCh. 19 - Prob. 14RQCh. 19 - Prob. 15RQCh. 19 - Prob. 16RQCh. 19 - Prob. 17RQCh. 19 - Prob. 18RQCh. 19 - Prob. 19RQCh. 19 - Prob. 20RQCh. 19 - Prob. 21RQCh. 19 - Prob. 22RQCh. 19 - Prob. 23RQCh. 19 - Prob. 24RQCh. 19 - Prob. 25RQCh. 19 - Prob. 26RQCh. 19 - Prob. 27RQCh. 19 - Prob. 28RQCh. 19 - Prob. 29RQCh. 19 - Prob. 30RQCh. 19 - Prob. 31RQCh. 19 - Prob. 32RQCh. 19 - Prob. 33RQCh. 19 - Prob. 34RQCh. 19 - Prob. 35RQCh. 19 - Prob. 36RQCh. 19 - Prob. 37RQCh. 19 - Prob. 38RQCh. 19 - Prob. 39RQCh. 19 - Prob. 40RQCh. 19 - Prob. 41RQCh. 19 - Prob. 42RQCh. 19 - Prob. 43RQCh. 19 - Prob. 44RQCh. 19 - Prob. 45FBCh. 19 - Prob. 46FBCh. 19 - Prob. 47FBCh. 19 - Prob. 48FBCh. 19 - Prob. 49FBCh. 19 - Prob. 50FBCh. 19 - Prob. 51FBCh. 19 - Prob. 52FBCh. 19 - Prob. 53FBCh. 19 - Prob. 54FBCh. 19 - Prob. 55SACh. 19 - Prob. 56SACh. 19 - Prob. 57SACh. 19 - Prob. 58SACh. 19 - Prob. 59SACh. 19 - Prob. 60TQCh. 19 - Prob. 61TQCh. 19 - Prob. 62TQCh. 19 - Prob. 63TQCh. 19 - Prob. 64TQCh. 19 - Prob. 65TQCh. 19 - Prob. 66TQCh. 19 - Prob. 67TQCh. 19 - Prob. 68TQCh. 19 - Prob. 69TQCh. 19 - Prob. 70TQCh. 19 - Prob. 71TQCh. 19 - Prob. 72TQCh. 19 - Prob. 73TQ
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