Q69.Match List I with List II
| LIST I | LIST II |
|---|---|
| A. Aversion to water | I. DNA content of cells |
| B. Levinthal paradox | II. Hydrophobic effect |
| C. C-value paradox | III. Protein conformations |
| D. Ramachandran plot | IV. Protein folding |
Choose the correct answer from the options given below:
(1) A-I, B-IV, C-II, D-III
(2) A-II, B-IV, C-I, D-III
(3) A-I, B-III, C-II, D-IV
(4) A-III, B-II, C-I, D-IV
Levinthal paradox addresses protein folding pathways, while C-value paradox concerns genome size. The correct answer is option (2): A-II, B-IV, C-I, D-III.
Match Analysis
A. Aversion to water → II. Hydrophobic effect. Correct—hydrophobics avoid water, driving protein core formation.
B. Levinthal paradox → IV. Protein conformations. Correct—random search of ~10^100 conformations impossible in biological time; folding follows guided pathways.
C. C-value paradox → I. DNA content of cells. Correct—genome sizes uncorrelated with organism complexity (e.g., amoeba > human).
D. Ramachandran plot → III. Protein folding. Correct—φ/ψ angle map shows sterically allowed backbone conformations for folding prediction.
Option Breakdown
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(1) A-I, B-IV, C-II, D-III: Wrong—A ≠ DNA content; C ≠ hydrophobic.
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(2) A-II, B-IV, C-I, D-III: Correct—all matches precise.
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(3) A-I, B-III, C-II, D-IV: Wrong—A, B, C mismatched.
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(4) A-III, B-II, C-I, D-IV: Wrong—A ≠ conformations; B ≠ hydrophobic; D ≠ folding.
Aversion to water defines the hydrophobic effect (A-II), while Levinthal paradox questions how proteins navigate 10^100 conformations to fold in seconds (B-IV).
Perfect Matches Explained
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Hydrophobic effect: Non-polar residues bury internally, stabilizing folds.
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Levinthal paradox: Resolved by funnel-shaped energy landscapes guiding local→global structure.
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C-value paradox: Onion (16 Gb) > human (3 Gb) DNA despite simpler biology.
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Ramachandran plot: Backbone dihedral angles (φ -60°, ψ -45° α-helix) predict secondary structure.
Why Option (2) Wins
Each term uniquely pairs: hydrophobicity ≠ DNA; Levinthal ≠ conformations specifically; Ramachandran enables folding prediction.
Exam Strategy: Memorize Levinthal=conformations (search space); C-value=genome size disconnect.
