Ch 29 – Plant Structure and Function Vocabulary Review Ch 29 – Plant Structure and Function

In higher plants, the fundamental tissue that is composed of thin-walled living cells that function in photosynthesis and storage Parenchyma

A group of elongated, thick-walled plant cells that support the growth of leaves and stems Collenchyma

A type of plant tissue composed of cells that have thickened secondary cell walls that function in plant support Sclerenchyma

The outer surface layer of cells of a plant or animal Epidermis

A waxy or fatty and watertight layer on the external wall of epidermal cells Cuticle

A thick-walled, cylindrical cell with tapered ends that is found in xylem and that provides support and conducts water and nutrients Tracheid

In plants, the thin, porous areas of a tracheid cell wall Pit

In plants, one of the cellular components of a xylem vessel Vessel element

In plants, a tube-like structure in the xylem that is composed of connected cells that conduct water and mineral nutrients Vessel

One of the component cells of a sieve tube, which is found mainly in flowering plants Sieve tube member

In the phloem of a flowering plant, a conducting tube that is made up of a series of sieve-tube members stacked end to end Sieve tube

A region that connects two sieve cells and that has one or more sieve areas, which consist of clusters of pores through which the cytoplasm of the cells is connected and through which materials are transported Sieve plate

A specialized parenchyma cell that assists in transport and that gives rise to sieve tubes in angiosperms Companion cell

A region of undifferentiated plant cells that are capable of dividing and developing into specialized plant tissues Meristem

The growing region at the tips of stems and roots in plants Apical meristem

Dividing tissue that runs parallel to the long axis of a stem or a root Lateral meristem

In a plant, the lateral meristem that produces secondary xylem and phloem Vascular cambium

A layer of tissue under the cork layer where cork cells are produced Cork cambium

In biology, a joint between two adjacent sections in the stem of a plant where buds form and leaves or branches start to grow; usually marked by a knot or swelling Node

The part of a plant stem between two consecutive nodes Internode

A shoot or flower that has immature leaves folded in the growing tip Bud

A modified leaf that forms a protective covering for a bud until it opens Bud scale

The tissue that is located in the center of the stem of most vascular plants and that is used for storage Pith

Secondary xylem produced in gymnosperm and dicot stems Wood

Dark wood in center of tree Heartwood 26

Functional, often lighter-colored wood nearer the outside of the trunk Sapwood

The protective outside covering of woody plants, consisting of cork, cork cambium, and phloem Bark

Wood formed during the spring when water is plentiful; vascular cambium can form new xylem with cells that are wide and thin walled Springwood

Wood produced by vascular cambium in summer, when water is limited; smaller cells with thicker walls Summerwood

In secondary xylem (wood), the growth ring formed in one season Annual ring

A part of a plant that makes sugars and other organic compounds and from which these compounds are transported to other parts of the plant Source

Any place where a plant stores or uses organic nutrients, such as sugar or starches Sink

The movement of soluble nutrients from one part of a plant to another Translocation

Pressure-flow hypothesis An explanation for the movement of carbohydrates in the phloem of plants; holds that carbohydrates are actively transported into sieve tubes Pressure-flow hypothesis

The process by which plants release water vapor into the air through stomata; also the release of water vapor into the air by other organisms Transpiration

Cohesion-tension theory An explanation for the movement of water up the stem xylem of tall plants; states that water is pulled up the xylem vessels by the cohesive force between the water molecules and the adhesion of the water molecules to the rigid vessel walls Cohesion-tension theory

An organ of climbing plants that grows in spiral form and wraps around another body to help support the plant Tendril

The broad, flat portion of a typical leaf Blade

The stalk that attaches a leaf to the stem of a plant Petiole

A leaf that has an undivided blade Simple Leaf

A type of leaf in which the blade is divided into leaflets Compound leaf

One segment of a compound leaf Leaflet

In leaves, the tissue between epidermal layers, where photosynthesis occurs Mesophyll

In plants, the layer of vertically elongated cells that contains chloroplasts, that is located beneath the upper epidermis of leaves, and that participates in photosynthesis Palisade mesophyll

Inside a leaf, the tissue that is made up of loosely arranged parenchyma cells that contain chloroplasts and are surrounded by air spaces that promote the diffusion of oxygen, carbon dioxide, and water throughout the leaf Spongy mesophyll

In plants, a bundle of vascular tissue that transports fluids and nutrients Vein

The arrangement of veins in a leaf Venation

A parallel arrangement of veins; typical of the leaves of monocots Parallel venation

A nonparallel, branching network of veins that is typical of the leaves of dicots Net venation

One of a pair of specialized cells that border a stoma and regulate gas exchange Guard cell