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Genetics and heredity — Question 18

QCAA 2023, Paper 1 · 1 mark

Q18 · 2023 · Paper 1Unclassified1 mark

QUESTION 18

Calcium chloride (CaCl,) is a chemical used in bacterial transformation. An experiment was conducted to determine how the concentration of calcium chloride affects the transformation efficiency of large and small plasmids. Error bars show standard error.

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The data suggests that

(A) the optimal concentration for transforming small plasmids is 0.15 M.

(B) transformation efficiency is highest at concentrations greater than 0.1 M.

(C) large plasmids have higher transformation efficiency than small plasmids.

(D) there is less variation in transformation efficiency of small plasmids when concentration is less than 0.2 M.

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