When the dna ladder twists the way it normally does the shape of the molecule is called a

The sidwa of the DNA ladder are made up of alternating sugars and phosphate groups. A is always paired with T and G is always paired with C. Paired bases are held together by weak bonds called hydrogen bonds, and when the DNA ladder twists the way it normally does, the shape of the molecule is called a double helix.

1. is geographic distribution

2 is increasing complexity

3 is transitional forms