In the DNA molecules

In the DNA molecules
  1. There are two strands which run antiparallel-one in $5^{\prime} \rightarrow 3^{\prime}$ direction and other in $3^{\prime} \rightarrow$ $5+$
  2. The total amount of purine nucleotides and pyrimidine nucleotides is not always equal
  3. There are two strands which run parallel in the $5^{\prime} \rightarrow 3^{\prime}$ direction
  4. The proportion of Adenine in relation to thymine varies with the organism

Solution

The 2 strands of DNA are antiparallel one in $5^{\prime}-3^{\prime}$ direction and the other in $3^{\prime}-5^{\prime}$ direction.

Asked in: NEET 2008 (Mains)

Practice more Molecular Basis of Inheritance questions on Aicharya