Campbell Biology Chapter 35

Apical Bud

A bud at the tip of a plant stem, also called a terminal bud

Secondary growth

Growth produced by lateral meristems, thickening the roots and shoots of woody plants

Axillary Bud

A structure that has the potential to form a lateral shoot, or branch. The bud appears in the angle formed between a lead and a stem.

Primary Growth

Growth produced by apical meristems, lengthening stems and roots.

Pith

Ground tissue that is internal to the vascular tissue in a stem, in many monocot roots, parenchyma cells that form the central core of the vascular cylinder

Internode

A segment of a plant stem between the points where leaves are attached

Ground tissue system

Plant tissues that are neither vascular, nor dermal, fulfilling a variety of functions, such as storage, photosynthesis, and support.

Tissue

An integrated group of cells with a common structure, function, or both

Endodermis

In plant roots, the innermost layer of the cortex that surrounds the vascular cylinder

Shoot syste

The aerial portion of a plant body, consisting of stems, leaves, and flowers

Lateral meristem

A meristem that thickens the roots and shoots of woody plants, the vascular cambium and cork cambium are lateral meristems

Sclereid

A short, irregular sclerenchyma cell in nutshells and seed coats. Sclereids are scattered throughout the parenchyma of some plants.

Stele

The vascular tissue of a stem or root.

Node

A point along the stem of a plant at which leaves are attached

Xylem

Vascular plant tissue consisting mainly of tubular dead cells that conduct most of the water and minerals upward from the roots to the rest of the plant.

Petiole

The stalk of a leaf, which joins the leaf to a node of the stem.

Mesophyll

Leaf cells specialized for photosynthesis.

Apical dominance

Tendency for growth to be concentrated at the tip of a plant shoot, because the apical bud partially inhibits axillary bud growth

Companion Cell

A type of plant cell that is connected to a sieve-tube element by many plasmodesmata and whose nucleus and ribosomes may serve one or more adjacent sieve-tube elements

Root cap

A cone of cells at the tip of a plant root that protects the apical meristem

Cork cambium

A cylinder of meristematic tissue in woody plants that replaces the epidermis with thicker, tougher cork cells

Sclerenchyma cell

A rigid, supportive plant cell type usually lacking a protoplast and possessing thick secondary walls strengthened by a lignin at maturity.

Dermal tissue system

The outer protective covering of plants

Apical meriistem

Embryonic plant tissue in the tips of roots and buds of shoots. The dividing cells of an apical meristem enable the plant to grow in length

Vascular tissue system

A transport system formed by xylem and phloem through a vascular plant. Xylem transports water and minerals; phloem transports sugars, the products of photosynthesis

Collenchyma cell

A flexible plant cell type that occurs in strands or cylinders that support young parts of the plant without restraining growth

parenchyma cell

A relatively unspecialized cell type that carries out most of the metabolism, synthesizes and stores organic products, and develops into a more differentiated cell type.

Vascular Cambium

A cylinder of meristematic tissue in woody plants that adds layers of secondary vascular tissue called secondary xylem and secondary phloem

Taproot

A main vertical root that develops from an embryonic root and gives rise to lateral roots

Epidermis

The dermal tissue system of nonwoody plants, usually consisting of a single later of tightly packed cells.

Root hair

A tiny extension of a root epidermal cell, growing just behind the root tip and increasing ssurface area for absorption of water and minerals

Cortex

The outer region of cytoplasm in a eukaryotic cell, lying just under the plasma membrane, that has a more gel-like consistency than the inner regions due to the presence of multiple microfilaments

Bark

All tissues external to the vascular cambium, consisting mainly of the secondary phloem and layers of periderm.