Question

Antiparallel strands of a DNA molecule means that ______.

Options

• one strand turns anticlockwise

• phosphate groups at the ends of the two DNA strands share the same position

• phosphate groups at the start of two DNA strands are in opposite position

• one strand turns clockwise

Answer 1

Antiparallel strands of a DNA molecule means that phosphate groups at the start of two DNA strands are in opposite position.

Explanation:

Antiparallel strands have opposite polarity, with their 5′ and 3′ ends oriented in opposite directions. The choices about clockwise or anticlockwise turning do not describe strand polarity.