Question : Assertion : The sugar phosphatebackone of two chains in DNA double helix show anti-parallel polarity. Reason : The phosphodiester bondsin one strand go from a 3' cardon of one nucleotide to a 5, carbon of adjacent nucleotide, whereas those in complementary strand go vice versa.

Question : Assertion : The sugar phosphatebackone of two chains in DNA

1.	Question : Assertion : The sugar phosphatebackone of two chains in DNA double helix show anti-parallel polarity. Reason : The phosphodiester bondsin one strand go from a 3' cardon of one nucleotide to a 5, carbon of adjacent nucleotide, whereas those in complementary strand go vice versa.
Answer» If both ASSERTION and reason are true and reason is the correct explanation of assertion If both assertion and reason are true butreason is notthe correct explanation of assertion If assertion is true but reason is false if both assertion and reason are false. Solution :The back BONE of a DNA chain or strand is built up of alternate deoxyribose sugar and phosphate groups The phosphate group is CONNECTED to carbon 5' of the sugar residue of its own nucleoide and carbon 3' of the sugar residue of the next nucleotide by (3' `to` 5') phosphiodister bonds.The two DNA chains are antiparallel , that is , they run PRALLEL but in opposite DIRECTIONS In one chain the direction . In one chain the direction is 5' `to` 3' , while in opposite one , it is 3' `to` 5'