Vascular and Nonvascular Plant Structures and Functions


Openings in the outer cell layer of leaf surfaces and some stems that allow the exchange of water, carbon dioxide, oxygen, and other gases between a plant and its environment.

Vascular Tissue

Specialized tissue that transports water, food, and other substances in vascular plants and can also provide structure and support.

Vascular Plant

Type of plant with vascular tissues adapted to land environments; most widely distributed type of plant on Earth.

Nonvascular Plant

Type of plant that lacks vascular tissues, moves substances slowly from cell to cell by osmosis and diffusion, and grows only in a damp environment.


Adaptive reproductive structure of some vascular plants that contains an embryo, nutrients for the embryo, and is covered by a protective coat.


Liverwort with a fleshy, lobed body shape.


Compact cluster of spore-bearing structures in some seedless vascular plant sporophytes.


Plant that lives anchored to an object or to another plant.


Fern’s thick underground stem that functions as a food-storage organ.


Sac or case in which fungal spores are produced.


Fern structure formed by clusters of sporangia, usually on the undersides of a frond.


Seed structure that stores food or helps absorb food for the sporophyte of vascular seed plants.


Feature that contains male or female reproductive structures of cycads and other gymnosperms.


Plant that completes its life span in one growing season or less.


Plant with a two-year life span.


Plant that can live for several years.

Parenchyma Cell

Spherical, thin-walled cell found throughout most plants that can function in photosynthesis, gas exchange, protection, storage, and tissue repair and replacement.

Collenchyma Cell

Often elongated plant cell that provides flexibility for the plant, support for surrounding tissues, and functions in tissue repair and replacement.

Sclerenchyma Cell

Plant cell that lacks cytoplasm and other living components when mature, leaving thick, rigid cell walls that provide support and function in transport of materials.


Region of rapid cell division in plants; produces cells that can develop into many different types of plant cells.

Vascular Cambium

Thin cylinder of meristematic tissue that produces new transport cells.

Cork Cambium

Meristematic tissue that produces cells with tough cell walls that form the protective outside layer on stems and roots.


Dermal tissue that makes up a plant’s outer covering.

Guard Cell

One of a pair of cells that function in the opening and closing of a plant’s stomata by changes in their shape.


Vascular plant tissue that transports water and dissolved minerals away from the roots throughout the plant and is composed of vessel elements and tracheids.

Vessel Element

Elongated, tubular plant cell that forms xylem strands (vessels) and conducts water and dissolved substances.


Long, cylindrical plant cell in which water passes from cell to cell through pitted ends.


Vascular plant tissue composed of sieve tube members and companion cells that conducts dissolved sugars and other organic compounds from the leaves and stems to the roots and from the roots to the leaves and stems.

Sieve Tube Member

Nonnucleated, cytoplasmic cell of the phloem.

Companion Cell

Nucleated cell that helps the mature sieve tube member function in transporting dissolved substances in the phloem of vascular plants.

Ground Tissue

Plant tissue consisting of parenchyma, collenchyma, and sclerenchyma.

Root Cap

Layer of parenchyma cells that covers the root tip and helps protect root tissues during growth.


Layer composed of ground tissues between the epidermis and vascular tissue of a root.


Cell layer at the inner boundary of the cortex; regulates the material that enters the plant’s vascular tissues.


Plant tissue that produces lateral roots.


Stalk that connects a plant’s blade to the stem.

Palisade Mesophyll

Leaf-tissue layer that contains many chloroplasts and is the site where most photosynthesis takes place.

Spongy Mesophyll

Loosely packed, irregularly shaped cells with spaces around them located below the palisade mesophyll.


Process in which water evaporates from the inside of leaves to the outside through stomata.


Plant hormone that moves in only one direction away from the site where it was produced and can stimulate the elongation of cells.


Group of plant hormones that are transported in vascular tissue and that can affect seed growth, stimulate cell division, and cause cell elongation.


Gaseous plant hormone that affects the ripening of fruits.


Plant hormone that promotes cell division by stimulating production of proteins required for mitosis and cytokinesis.

Nastic Response

Reversible, responsive movement of a plant that occurs independent of the direction of the stimulus.


Response to an external stimulus in a specific direction.