Exchange & Transport in Plants

This set of flashcards covers essential vocabulary and concepts regarding plant exchange and transport mechanisms, focusing on xylem and phloem functions.

Gas Exchange

The process by which plants exchange gases, mainly occurring through stomata, lenticels, and spaces between cells.

Xylem

Tissue responsible for the transport of water and dissolved inorganic nutrients; operates unidirectionally from roots to tips.

Phloem

Tissue responsible for the transport of photosynthates (sugars) and hormones; functions multidirectionally.

Transpiration Pull

A theory describing the movement of water in xylem due to combined effects of cohesion, adhesion, and tension.

Capillary Action

The ability of water to travel upward through narrow spaces due to cohesive and adhesive forces.

Bulk Flow

The process of mass movement of fluids within the phloem, driven by pressure differences.

Source vs Sink

Concept describing the origins (sources) and destinations (sinks) of nutrients and water in plants.

Guard Cells

Specialized cells that control the opening and closing of stomata, regulating gas exchange.

Osmosis

Movement of water across a semipermeable membrane from an area of low solute concentration to high.

Cohesion and Adhesion

Cohesion refers to water molecules attracting each other, while adhesion is the attraction between water molecules and other substances.

Turgor Pressure

The pressure exerted by water inside the plant cell, important for maintaining cell structure and driving growth.

Parenchyma

A type of simple tissue in plants, comprising undifferentiated cells involved in storage, photosynthesis, and tissue repair.

Sclerenchyma

Complex tissue that provides structural support, composed of fibers or sclereids.

Collenchyma

A type of simple tissue that provides flexible support to young stems and leaves.