What happens to water transport if an air bubble forms within the xylem?

Explanation

The force of attraction of water molecules (cohesion) in the column is a result of the hydrogen bonds between them. An air bubble in the xylem interrupts the continuity of water by displacing some of the molecules they become too far from each other to form hydrogen bonds. Water above the bubble may be pulled up, but it will not be replaced by water from below the bubble because the cohesive force has been broken. Thus, a xylem channel with an air bubble can no longer transport water upward from the soil.