What aspects of the structure of DNA are explained by this model? A. Paired nucleotides are held together by covalent bonds.
B.
Adenine is paired with thymine, and guanine is paired with cytosine.
C. Paired nucleotides are held together by hydrogen bonds.
D. The two strands of DNA each have phosphate-sugar backbones
E. The numbers of each nucleotide determine genetic information

By water evaporation from the leaves is created a negative pressure at the top of the tree that promotes the ascension  of the water through channels that are called xylem. there are also two molecule forces that are involved: the intra-water molecules cohesion (water molecules stick to each other) and the adhesion when the water molecules stick to the channels they are running in. this is what enables water to go from the roots to the top of a tall tree.