BIOCHEMISTRY
9th Edition
ISBN: 2818440090622
Author: BERG
Publisher: MAC HIGHER
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Chapter 32, Problem 10P
Interpretation Introduction
Interpretation:
The unusual thing about the beginning of mRNA in the λ repressor gene should be determined.
The efficiency of translation of this gene should be determined.
Concept introduction:
λ repressor inactivated state binds to OR1 and OR2 sites and inhibits the transcription of phage gene. On the other hand, Cro protein binds to the same sites, to which λ repressor binds. In this way, the Cro protein inhibits the action of λ repressor.
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Students have asked these similar questions
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
0
➜ (degrees)
180
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