Water Potential exam Flashcards

The potential energy of water to move between two environments, determined by solute potential and pressure potential.

Water moves from areas of high water potential to areas of low water potential.

The solute concentration relative to pure water; high solute concentration means low solute potential.

Water potential is measured in megapascals (MPa).

The physical pressure on water, which can be positive or negative.

A theory that explains how evaporation creates negative pressure, pulling water upward through the xylem.

The process of water evaporation from plant leaves, which helps pull water up from the roots.

The pressure inside a plant cell due to water pushing the cell contents against the cell wall.

A waxy layer in plant roots that regulates ion flow and solute concentration by blocking the apoplastic route.

Sugars are transported from sources to sinks via bulk flow in the phloem, facilitated by pressure differences.

Channels in cell membranes that facilitate the efficient movement of water.

It forces water into endodermal cells, allowing them to act as filters to control ion flow and solute concentration.

The movement of molecules along a pressure gradient, such as the movement of xylem sap or phloem sap.

The balance plants must find between conserving water and maximizing photosynthesis.

A theory suggesting that positive pressure builds up in the root xylem due to increased water absorption relative to transpiration.

Stomata control gas exchange and water evaporation by opening and closing.

The pathway through the cytosol of cells, linked by plasmodesmata, for water movement.

Proton pumps create a proton gradient that allows the proton-sucrose symporter to load sugar into the phloem.

The bulk flow of sugars from source to sink in the phloem.

The exudation of water droplets from leaves due to high root pressure.

The force between water molecules at the air-water interface, creating a tension across the surface.

The cohesion-tension theory, where evaporation creates negative pressure that pulls water upward.

The process of sugars entering the phloem via secondary active transport.

Lignified cell walls provide structural support to withstand the negative pressure generated by water transport.

The ability of water to move through narrow spaces due to adhesion, cohesion, and surface tension.

The xylem transports water and dissolved minerals from the roots to the rest of the plant.

The balance between conserving water and maximizing photosynthesis in plants.

A theory explaining the movement of phloem sap from source to sink due to pressure differences.

The attraction between like molecules, such as water molecules clinging to each other.