Question

1. describe the overall structure of a dna molecule. what shape does it take?
2. why are the hydrogen bonds between the bases a better option for holding a dna molecule together versus say covalent bonds?

Explanation:

1. A DNA molecule has a double - helix structure. It consists of two polynucleotide chains that wind around each other. The sugar - phosphate backbones are on the outside and the nitrogenous bases are on the inside, forming base pairs through hydrogen bonds.
2. Hydrogen bonds are better for holding a DNA molecule together than covalent bonds because hydrogen bonds are weaker and more easily broken. This allows for processes like DNA replication and transcription to occur, where the two strands need to separate temporarily. Covalent bonds are very strong and would make it difficult to separate the strands for these essential biological processes.

Answer:

1. A DNA molecule has a double - helix shape.
2. Hydrogen bonds are weaker and allow for strand separation during replication and transcription, while covalent bonds would be too strong for this.