Question

1. ligase joins fragments together by connecting their backbones. this means that it connects ____________. nitrogen bases sugar to phosphate guanine to cytosine adenine to thymine dna to rna 12. what would happen if ligase were absent? dna would be unable to unzip. the nucleotides in the cell would disappear. new dna strands would be made of disconnected pieces. base pairs would not be able to form. rna would be found mixed in with dna strands.

Explanation:

1. Ligase functions in DNA replication by forming phosphodiester bonds between the sugar - phosphate backbones of DNA fragments. It doesn't connect nitrogen bases directly, nor does it connect base - pairs (guanine - cytosine, adenine - thymine) or DNA to RNA.
2. Without ligase, the Okazaki fragments on the lagging strand during DNA replication would not be joined together, resulting in new DNA strands made of disconnected pieces. DNA unzipping is done by helicase, nucleotides don't disappear due to lack of ligase, base - pair formation is not directly related to ligase function, and RNA being mixed with DNA strands is not a direct consequence of ligase absence.

Answer:

1. Sugar to phosphate
2. New DNA strands would be made of disconnected pieces.