FAQ -- rec.gardens.ecosystems: Appendix E
A Glossary of Botanical Terms
- Abscission (ab-sizh'un)the controlled separation of leaves,
flowers and fruit from plants
- Adventitious root (ad-ven-tish'uss root) a root arising in an
unexpected position such as along stems or on leaves
- Adventitious shoot (ad-ven-tish'uss shoot) a shoot arising in an
unexpeced position such as in internodes or on roots
- Alternation of generations (ol-tur-nay'shun-uv-jen-ur-ay'shunz)
- Alternation between a haploid gametophyte phase and a diploid
sporophyte phase in the life cycle of sexually reproducing organisms
- Angiosperm (an'jee-oh-spurm) a plant whose seeds develop within
ovaries that mature into fruits
- Annual(an'you-ul) a plant completing its life cycle within a
single growing season
- Anther (an'-thur) The pollen-bearing part of a stamen
- Antheridium (an-thur-id'ee-um)the male sex organs of plants
other than Gymnosperms and Angiosperms
- Apical bud (ay'pi-kul bud) a bud at the tip of a stem
- Apical dominance(ay'pi-kul dom-in-ance') the inhibition of
axillary bud growth by the apical bud
- Apical meristem (ay'pi-kul mair'i-stem) a region of actively
dividing cells at the tip of a growing root or stem
- Archegonium (ahr-kuh-goh'nee-um)the female sex organ of plants
other than Angiosperms
- Auxin (awk'sin) a plant hormone that controls cell elongation
- Axil (ak'sil) the angle between the upper surface of a leaf and
the stem to which it is attached
- Axillary bud (ak'sil-air-ee bud) a bud located in an axil at the
base of a leaf
- Bark (bahrk) tissues of a woody stem between the vascular
cambium and the exterior
- Biennial (by-en'ee-ul) a plant completing its life-cycle within
two growing seasons
- Biotechnology (by-oh-tek-nol'-oh-jee) the manipulation of
organisms, tissues, cells or molecules for specific applications
- Bolting (bolt'-ing) the rapid growth of a stem prior to
flowering
- Bract (brakt) a modified leaf arising below a flower or
inflorescence
- Budding (bud'ing) a form of grafting in which the scion is a bud
surrounded by a small shield of tissue
- Bulb (buhlb) an underground food-storage organ that is
essentially a modified bud growing from a solid, bottom basal plate
surrounded by layers of fleshy leaves called scales'.
- Callus (kal'uss) a corky tissue developed by woody species to
cover wounds
- Calyx (kay'liks) collective term for the sepals of a flower
- Cambium (kam'bee-um) a meristem producing secondary tissues; see
cork cambium and vascular cambium
- Carbon-Fixing Reactions (kahr-bon fixing ree-ak'shunz) a
cyclical series of chemical reactions that utilizes carbon dioxide
and energy generated during the light reactions of photosynthesis to
produce sugars
- Carpel (kahr'pul) an ovule-bearing unit that is part of a pistil
- Cell (sel) the basic strutural and functional unit of living
organisms; in plants it consists of protoplasm surrounded by a cell
wall
- Chlorophyll (klor'uh-fil) green pigments located in the
chloroplasts essential to photosynthesis
- Chloroplast (klor'uh-plast) a cellular body in which photo-
synthesis occurs
- Chromosome (kroh'muh-sohm) a thread-like structure bearing genes
in a cell nucleus
- Cork (kork) the protective, outer tissue of bark
- Cork cambium (kork kam'bee-um) a layer of cells between the
exterior of a woody root or stem and the central vascular tissue;
also called phellogen
- Corm (korm) a short, swollen, underground stem in which food is
stored
- Cormel (kor'mel) a small undeveloped corm
- Corolla (kuh-rahl'uh) collective term for the petals of a flower
- Corona (kuh-ro'nah) an extra whorl of flower parts between the
corolla and the stamens
- Cortex (kor'teks) the tissue in roots and stems just inside the
epidermis
- Cotyledon (kot-uh-lee'dun) a seed leaf that either stores or
absorbs food
- Cultivar (kul'ta-var) a cultivated variety produced by
horticultural techniques
- Deciduous (duh-sij'yu-wuss) shedding leaves in one season
- Dicot (dy'-kot) a class of angiosperms having two cotyledons
- Differentially permeable membrane (dif-uh-rensh'uh-lee
pur'mee-uh-bul mem'brayn) a membrance through which different
substance diffuse at different rates
- Diploid (dip'loyd) having two sets of chromosomes
- DNA (dee-en-ay) deoxyribonulceic acid, the carrier of genetic
information in cells and viruses
- Dormant (dor'mant) a state of reduced cellular activity
- Embryo (em'bree-oh) an immature plant within a seed
- Endodermis (en-doh-dur'mis) a singler layer of cells surrounding
the stele in roots and some stems
- Epidermis (epe-uh-dur'mis) the exterior tissue, usually one cell
thick, of leaves, young stems and roots, and other parts of plants
- Epiphyte (ep'uh-fyt) an organism that is attached to and grows
on another organism without parasitizing it
- Etiolation (ee-tee-oh-lay'shun) the condition of a plant when
grown without enough light; its stem is pale and elongated, the
leaves are undeveloped
- Exine (ek'seen) the outer layer of the wall of a pollen grain or
spore
- F1 (eff wun) first filial generation; the offspring of a cross
between two parent plants
- F2 (eff too) second filial generation; the offsdpring of F1
plants
- Filament (fil'uh-mint) threadlike body of certain algae and
fungi; also the stalk portion of the stamen
- Frond (frond) a fern leaf; occassionally also applied to palm
- Gamete (gam'eet) a sex cell; sperm or egg
- Gametophyte (guh-me'toh-fyte) a haploid,gamete-producing plant
in the alternation of generations
- Genetic engineering (juh'net'ik en-juh-neer'ing) the
introduction by artifical means, of genes from one form of DNA into
another form of DNA
- Gibberellin (jib-uh-rel'in) a plant hormone that regulates
several processes including internode elongation and cell
enlargement
- Graft (graft) the union of a segment of a plant, the scion, with
a rooted portion, the stock
- Guard Cells (gahrd sel) one of a pair of cells surrounding a
stoma
- Gymnosperm (jim'noh-spurm) a plant whose seeds are not enclosed
within an ovary during their development
- Haploid (hap'loyd) having one set of unpaired chromosomes
- Heartwood (hahrt'wood) the central, dark colored portions of
non-living wood
- Herbaceous (hur-bay'shuss) soft, green and containing little
woody tissue
- Humus(hum'us) organic mattter in the soil derived from the
decomposition of plant and animal remains
- Hybrid (hy'brid) offspring of two parents that differ in one or
more genes
- Hypha (pl. hyphae)(hy'fuh; pl. hy'fee) a singler, usually
tubular, thread-like filament of a fungus
- Imbibition (im-buh-bish'um) The process of water absorption by a
dry substance or structure, causing it to swell
- Inflorescence (in-fluh-res'ints)a collective term for a group of
flowers attached to a common axis
- Integument (in-teg'yu-mint) the outermost layer of an ovule;
usually develops into a seed coat; a gymnosperm ovule usually has a
single integument, and an angiosperm ovule usually has two
integuments
- Internode (in'tur-node) the segmnent of a stem between two nodes
- Lateral meristem (lat'uh-rul mair'i-stem)a region where cells
divide, located along the length of a stem or root
- Layering (lay'er-ing) a method of plant propagation in which
adventitious roots are developed on an intact plant before the
rooted section is removed
- Leaf (leef) a flattened, usually photosynthetic structure
arranged in various ways on a stem
- Lenticel (lent'uh-sel) a small, gas-exchange opening in the cork
of a woody stem
- Lignin (lig'nin) a tough, plant substance that deposits in cell
walls
- Lipid (lip'id) a general term for fats, fatty substances, and
oils
- Loam (lo'm) a mixture of sand, silt, and clay
- Meiosis (my-oh'sis) a cell divisional process in which the
chromosome number is reduced by half
- Membrane (mem'brain) a thin, sheet4-like structure composed of
protein and fats surrounding the cytoplasm, organelles, and other
cell structures
- Meristem (mair'i-stem) a region in which undifferentiated cells
divide
- Middle lamella (mid'ul luh-mel'uh) a layer of material rich in
pectin that cements two adjacent cell walls together
- Mitosis (my-toh'sis) a cell divisional process in which the
chromosomes are duplicated
- Monocot (mon-oh-kot') a class of angiosperms whose seeds have a
single cotyledon
- Motile (moh'tul) capable of independent movement
- Mutations (myu-tay'shun) an inheritable change in a gene or
chromosome
- Mycelium (my-see'lee-um) a mass of fungal hyphae
- Mycorrhiza (my-kuh-ry'zuh)-(pl. mycorrhizae)(pl. my-kuh-ry'zee)
Beneficial soil fungi that live in a symbiotic relationship with
most plants
- Node (nohd) region of a stem where one of more leaves are
attached
- Nucleus (new'klee-uss) the body within a cell controlling its
activites, including inheritance
- Organelle (or-guh-nel') a membrane-bound body in the cytoplasm
of a cell; there are several kinds, each with a specific function
- Osmosis (oz-moh'sis) the diffusion of water or other solvents
through a differentially permeable membrane from a region of higher
concentration to a region of lower concentration
- Ovary (oh'vuh-ree) the enlarged basal portion of a pistil that
contains an ovule or ovules and usually develops into a fruit
- Ovule (oh'vyool) a structure of seed plants that contains a
female gametophyte and has the potential to develop into a seed
- Palisade cell (pal-uh-sayd' sel) a photosynthetic cell directly
beneath the upper leaf epidermis
- Parenchyma (puh-ren'kuh-muh) a thin-walled undifferentiated cell
- Pectin (pek'tin) a water-soluble organic compound occuring
primarily in the middle lamella; becomes a jelly when combined with
organic acids and sugar
- Pedicel (ped'i-sel) the stalk of an individual flower in an
inflorescence
- Peduncle (pee'dun-kul) the stalk of a solidary flower or the
main stalk of an inflorescence
- Perennial (per-ren'e-yel) A plant that lives through several
growing seasons
- Petiole (pet'ee-ohl) the stalk of a leaf pH (pee-aitch) a
measure of relative acidity or alkalinity
- Phellogen (fel'uh-jun) see cork cambium
- Pheromone (feh'uh-mohn) something produced by an organism that
facilitates chemical communication with another organism
- Phloem (flohm) the food-conducting tissue of plants
- Photoperiodism (foh-toh-pir'ee-ud-izm) the initiation of
flowering in response to relative lengths of day and night
- Photosynthesis (foh-toh-sin'thuh-sis) the process in which light
energy is used to form foods from carbon dioxide and water
- Pistil (pis'tul) a female reproductive structure of a flower;
composed of one or more carpels and consisting of an ovary, style,
and stigma
- Pith (pith) central parenchyma tissue of a dicot stem and
certain roots
- Polyploid (pahl-i-ploy'ed) having three or more sets of
chromosomes
- Quiescence (kwy'ess-ens) a state in which a seed or other plant
parts will not germinate or grow unless environmental conditions
normally required for growth are presnt
- Raceme (ra-sem') a branching arrangement where the flowers are
attached to the main stem by short stalks
- Radicle (rad'i-kuhl) the part of an embryo in a seed that
develops into a root
- Respiration (res-puh-ray'shun) the cellular breakdown of sugar
and other foods, accomplished by release of energy
- Rhizome (ry'zohm) an underground, horizontal stem that grows on
or just below the sosil surface
- Root (root) a plant organ that anchors the plant to the soil and
absorbs water and minerals
- Root cap (root kap) a protective, thimble-shaped mass of cells
at the tip of a growing root
- Root hair (root hair) a hair-like projection of a root's
epidermal cell
- Root nodule (root nod'uel) a small swelling on a root resulting
from invasion by nitrogen-fixing bacteria
- Sapwood (sap'wood) the lighter outer layers of wood that
transports water and minerals in a tree trunk
- Scion (sy'un) a segment of plant that is grafted onto a stock
- Seed (seed) a mature ovule containing an embryo and bound by a
protective coat
- Seed Coat (seed' koht) the outer boundary layer of a seed;
developed by the integument(s)
- Sepal (see'puhl) a unit of the calyx that frequently resembles a
reduced leaf; sepals often function in protecting the unopened
flower bud
- Shoot (shoot) a stem bearing leaves
- Sorus (sor'uss) an area of spore production on the underside of
a fern leaf
- Spike (spike) a branching arrangement where the flowers are
attached directly to the main stem
- Spore (spor) a reproductive cell that grows directly into a new
plant; sexual spores formed as a result of meiosis are often called
meiospores'; spores produced by mitosis are often called vegitative
spores'
- Sporophyte (spor'uh-fyt) a diploid, spore-producing plant in an
alternation of generations
- Stamen (stay'min) a pollen-producing structure of a flower;
consists of an anther and usually also a filament
- Stele (steel) the central cylinder of tissue in a stem or root;
usually consistinig of xylem and phloem
- Stem (stem) the leaf-and flower-bearing part of a plant
- Stigma (stig'muh) the pollen receptive area of a pistil; also
the eyespot of certain motile algae
- Stock (stok) a rooted plant into which a scion is inserted in
grafting
- Stollon (stoh'lun) a stem that grows vertically below the
surface of the ground; typically has relatively long internodes
- Stoma (pl. stomata)(stoh'muh; pl. stoh'mah-tuh) a pore in the
epidermis of leaves and herbaceous stems flanked by two guard cells
that regulate its opening and closing thus regulating gas exchange
and transpiration
- Style (styl) the structure that connects a stigma and an ovary
- Suberin (soo'buh-rin) a fatty plant substance present in the
walls of cork cells
- Symbiosis (sim-by-oh'siss) the living together for mutual
benefit of two or more organisms of different species
- Tissue (tish'yu) an aggregation of cells having a common
function
- Tissue Culture (tish'yu kult'yur) the culture of isolated living
tissue on an artificial medium
- Transpiration (trans-puh-ray'shun) loss of water in vapor form;
most transporation takes place through the stomata
- Tuber (too'bur) a swollen, fleshy underground stem (e.g., white
potato)
- Tuberous Roots (too'bur-us roots) swollen, fleshly roots
specialized to store nutrients
- Turgid (tur'jid) firm or swollen because of internal water
pressures resulting from osmosis
- Vascular Cambium (vas'kyu-lur kam'bee-um) a narrow cylinder of
cells that gives rise to secondary xylem and phloem; a lateral
meristem
- Vascular Tissue (vas'kyu-lur tish'yu) a group of fodd-or
water-conducting cells
- Wood (wood) the dense secondary xylem in stems and roots
- Xylem (zy'lim) The water-conducting tissue of plants
- Zygote (zy' goht) the product of the union of a sperm and an
egg