1. What allows the movement of water under tension in the xylem?A. Adhesion of water molecules to dissolved mineral saltsB. Cohesion of water molecules due to hydrogen bondingC. Adhesion between water molecules due to uneven sharing of chargesD. Cohesion between water molecules and other polar substances

The movement of water under tension in the xylem is primarily facilitated by two key properties of water: cohesion and adhesion.

Step 1: Cohesion of Water Molecules Due to Hydrogen Bonding Water molecules are polar, meaning they have a positive end and a negative end. This polarity allows water molecules to form hydrogen bonds with each other, creating a strong cohesive force. This cohesion helps water to move as a continuous column in the xylem without breaking apart.

Step 2: Adhesion of Water Molecules to Xylem Walls In addition to cohesion, water also exhibits adhesion, or the ability to stick to other substances. In the case of xylem, water molecules adhere to the walls of the xylem vessels. This adhesion helps to counteract the force of gravity and allows water to move upwards from the roots to the rest of the plant.

So, the correct answer to your question is both B. Cohesion of water molecules due to hydrogen bonding and C. Adhesion between water molecules due to uneven sharing of charges.