DNA polymerase contains a lysine residue that is important for binding to DNA. Mutations were found that converted this lysine to either glutamate, glycine, valine, or arginine. Which mutations would be predicted to be the most and least harmful to the ability of the enzyme to bind DNA?

	Most	Least
(A)	Valine	Aspartate
(B)	Glycine	Arginine
(C)	Arginine	Glycine
(D)	Glutamate	Arginine

TLS Online TPP Program

#Question id: 12995

#Unit 1. Molecules and their Interaction Relevant to Biology

Which of the following constraints affect the stability α-helix, 

a) the intrinsic propensity of an amino acid residue to form an α-helix.

b) the interactions between R groups.

c) the bulkiness of adjacent R groups.

d) the occurrence of Pro and Gly residues.

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#Question id: 12339

#Unit 10. Ecological Principles

If a species is a keystone predator, then its removal from a community should

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#Question id: 4957

#Unit 11. Evolution and Behavior

How many half-lives should have elapsed if 6.25% of the parent isotope remains in a fossil at the time of analysis?

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#Question id: 4590

#Unit 11. Evolution and Behavior

Which of the following statements describe evolution?

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#Question id: 8898

#Unit 9. Diversity of Life Forms

Which extant chordates are postulated to be most like the earliest chordates in appearance?