Question

The genetic counselor explains that understanding DNA's antiparallel structure helps predict how genetic information flows during gene expression. The two strands run in opposite directions, affecting how enzymes read genetic information. What does DNA's antiparallel organization enable in cellular processes?
Question 3 options:

Antiparallel strands allow enzymes to read genetic information in the correct direction for gene expression

Antiparallel organization is just a structural accident that doesn't affect cellular function

Only one strand contains genetic information; the other strand serves no functional purpose

DNA's antiparallel structure prevents any enzymes from accessing genetic information stored in the double helix

Answer 1

Antiparallel strands allow enzymes to read genetic information in the correct direction for gene expression.

Explanation: the two DNA strands run opposite (5'→3' vs 3'→5') and enzymes like DNA and RNA polymerases synthesize only in the 5'→3' direction. Antiparallel polarity therefore determines how replication and transcription proceed (leading vs. lagging strand, direction of transcription). The other choices are incorrect: both strands can carry information and the antiparallel arrangement is functionally important, not accidental, and it does not block enzyme access.