Plant Transport and Water Potential

A set of flashcards covering key vocabulary and concepts related to plant transport, water potential, and their mechanisms.

Active Transport

Movement of a substance against its concentration gradient; energy is needed.

Passive Transport

Movement of a substance down its concentration gradient; no energy is needed.

Osmosis

Diffusion of water down its water potential gradient.

Water Potential (Ψw)

Tendency of water to move from one place to another, measured in pressure and solute potential.

Turgor Pressure (Ψp)

Pressure exerted by water inside the cell against the cell wall.

Solute Potential (Ψs)

Pressure resulting from the presence of solutes in a solution; increases as solute concentration decreases.

Plasmolysis

Shrinking of the plasma membrane away from the cell wall due to loss of water.

Turgid Cell

A cell that is swollen and firm due to water uptake, which is favorable for plant health.

Flaccid Cell

A cell that is limp due to a loss of water; not ideal for plant health.

Transpiration

Loss of water vapor from plant leaves through stomata.

Cohesion

Attraction between water molecules, aiding in water transport in plants.

Adhesion

Attraction between water molecules and the walls of xylem cells, assisting water movement.

Xylem Transport

Transport of water and minerals from roots to leaves.

Phloem Transport

Transport of sugars from sources (e.g., leaves) to sinks (e.g., roots).

Casparian Strip

A band of cell wall material in the endodermis that prevents passive flow of materials into the vascular system.

Guttation

The exudation of drops of sap from the tips or edges of leaves.

Stomata

Pores on the leaf surface that regulate gas exchange and water loss.

Environmental Factors Affecting Transpiration

Factors such as temperature, humidity, wind velocity, sunlight, and carbon dioxide that influence the rate of transpiration.

Water Stress Responses

Plant adaptations such as dormancy or leaf modifications to cope with water scarcity.