Question

1. during replication, the strands of a double - stranded dna molecule separate from each other when bonds are broken between their —

• nitrogenous bases.
• amino acids.
• phosphate groups.
• 5 - carbon sugars.

Explanation:

In DNA, the two strands are held together by hydrogen - bonds between complementary nitrogenous bases. During replication, these hydrogen - bonds are broken to separate the strands. Amino acids are related to proteins, not DNA strand separation. Phosphate groups and 5 - carbon sugars are part of the DNA backbone and not involved in the separation of the two strands during replication.

Answer:

nitrogenous bases