Plant Organization: Morphology and Anatomy

Vocabulary practice flashcards covering plant organization, tissue systems, monocot vs. dicot morphology, root types, and comparative root, stem, and leaf anatomy.

Dermal Tissue System

The outer protective cell layer of a plant, primarily represented by the epidermis.

Ground Tissue System

The plant tissue system functioning primarily in storage, photosynthesis, and support; includes the cortex, pith, and mesophyll.

Vascular Tissue System

The plant tissue system responsible for the conduction of water, minerals, and organic nutrients throughout the plant; comprises xylem and phloem.

Xylem

The vascular tissue responsible for the conduction of water and dissolved minerals from roots to shoots.

Phloem

The vascular tissue responsible for transporting organic nutrients, especially sugars, throughout the plant.

Monocot (Monocotyledon)

An angiosperm characterized by one cotyledon, parallel leaf venation, vascular bundles scattered throughout stem ground tissue, floral parts in multiples of three, fibrous roots, and pollen with one pore or furrow.

Dicot (Dicotyledon)

An angiosperm characterized by two cotyledons, netlike leaf venation, stem vascular bundles arranged in a ring, floral parts in multiples of four or five, a taproot system, and pollen with three pores or furrows.

Cotyledon

An embryonic leaf present within the seed that stores or absorbs food reserves for the developing seedling.

Hypocotyl

The region of the embryonic axis located below the cotyledon attachment point and above the radicle.

Petiole

The stalk that attaches a leaf blade to the stem at a node, characteristic of dicot leaves.

Node

The specific point or region on a stem where leaves, lateral buds, or branches are attached.

Internode

The section of a plant stem between two successive nodes.

Axillary Bud

A bud positioned in the axil between the leaf petiole and the stem, giving rise to branches or flowers.

Simple Leaf

A leaf featuring a single, undivided blade, such as that seen in cottonwood.

Palmately Compound Leaf

A compound leaf in which all individual leaflets radiate outward from a single common central point.

Pinnately Compound Leaf

A compound leaf in which leaflets arise at multiple distinct locations along an elongated central axis.

Rachis

The elongated central axis of a pinnately compound leaf along which leaflets are attached.

Taproot System

A root system characterized by a single prominent, dominant primary root from which smaller lateral roots branch, typical of dicots.

Fibrous Root System

A root system made of numerous slender, similarly sized roots without a single dominant primary root, typical of monocots.

Adventitious Roots

Roots that originate from non-root plant tissues, such as stems or leaves.

Prop Roots

Adventitious roots developing from the lower stem nodes (such as in corn) that penetrate the soil to provide additional mechanical support.

Cortex

The ground tissue region situated between the dermal epidermis and the central vascular cylinder (stele) in roots and stems.

Stele

The central vascular cylinder of a root or stem, containing xylem, phloem, and associated tissues.

Endodermis

The innermost cellular layer of the root cortex that forms a selective barrier enclosing the vascular cylinder.

Pith

The central ground tissue composed of parenchyma cells, located in the center of dicot stems and monocot roots.

Internal root structure featuring a central solid core of primary xylem arranged in a star or cross shape, primary phloem situated between the xylem arms, and lacking a central pith

Dicot Root

Internal root structure characterized by a well-developed central parenchymatous pith surrounded by a ring of alternating xylem and phloem strands enclosed by an endodermis.

Monocot Root

Bundle Cap (Phloem Fibers)

A mass of sclerenchyma fibers located immediately external to the phloem within a stem's vascular bundle, providing mechanical strength.

Stem organization where discrete vascular bundles are scattered throughout ground tissue without clear separation into cortex and pith.

Monocot Stem

Stoma

A microscopic pore in the epidermis bordered by two guard cells that regulates gas exchange and water transpiration.