Chapter 6: Stems Flashcards
region of a stem where one or more leaves are attached
node
a stem region between nodes
internode
the conspicuous flattened part of a leaf (aka lamina) or seaweed
blade
the stalk of a leaf
petiole
the angle formed between a twig and the petiole of a leaf; normally the site of an axillary bud
axil
one of a pair of appendages of varying size, shape, and texture present at the base of the leaves of some plants
stipule
when something is shedding leaves annually
deciduous
the suberin-covered scar left on a twig when a leaf separates from it through abscission
leaf scar
a small scar left by a vascular bundle within a leaf scar when the leaf separates from its stem through abscission
bundle scar
an organ or structure at its earliest stage of development
primordium
central tissue of a dicot stem and certain roots; it usually consists of parenchyma cells that become proportionately less of the volume of woody plants as cambial activity increases the organ’s girth
pith
a primary tissue composed mainly of parenchyma; the tissue usually extends between the epidermis and the vascular tissue
cortex
a parenchyma-filled interruption in a stem’s cylinder of vascular tissue immediately above the point at which a branch of vascular tissue leading to a leaf occurs
leaf gap
thumbnail-shaped opening in the cylinder of vascular tissue
bud gap
a narrow, cylindrical sheath of cells that produces secondary xylem and phloem in stems and roots
-Cells continue to divide indefinitely, with the decisions taking place mostly in a plane parallel to the surface of the plant, and the secondary tissues add to the girth of the stem instead of to its length
vascular cambium
a narrow cylindrical sheath of cells between the exterior of a woody root or stem and the central vascular tissue; it produces cork to its exterior and phelloderm to its interior; aka phellogen
cork cambium
cell produced to the outside of the cork cambium
cork cell
a fatty substance found primarily in the cell walls of cork and the Casparian strips of endodermal cells
Suberin
tissue produced to the inside of the cork cambium
phelloderm
one of usually numerous, slightly raised, somewhat spongy groups of cells in the bark of woody plants; permit gas exchange between the interior of a plant and the external atmosphere
lenticel
the central cylinder of tissues in a stem or root; usually consists primarily of xylem and phloem
stele
an embryo leaf that usually either stores or absorbs food
cotyledon
a class of angiosperms whose seeds commonly have two cotyledons; frequently abbreviated to dicot
dicotyledon
a class of angiosperms whose seeds have a single cotyledon; commonly abbreviated to monocot
monocotyledon
a plant that completes its entire life cycle in a single growing season
annual
a strand of tissue composed mostly of xylem and phloem and usually enveloped by a bundle sheath
vascular bundle
a row of vascular tissue that extends horizontally across a stem
vascular ray
nonliving, usually darker-colored wood whose cells have ceased to function in water conduction
-Gives strength and support to the tree, but is not of much use
-Tree can live and function perfectly without it
heartwood
outer layers of wood that transport water and minerals in a tree trunk; usually lighter in color than heartwood
sapwood
tissues of a woody stem between the vascular cambium and the exterior
-Inner consists of primary and secondary phloem
-Outer (periderm) consists of cork tissue and cork cambium
bark
specialized cells or ducts resembling vessels; they form branched networks of latex-secreting cells in the phloem and other parts of plants
laticifer
an underground stem, usually horizontally oriented, that may be superficially rootlike in appearance but that has definite nodes and internodes
-Adventitious roots are produced along it
-May be a food-storage organ, as in irises, or it may be slender, as in many perennial grasses or some ferns
rhizome
a stem that grows horizontally along the surface of the ground; typically has long internodes
-Found with strawberries, saxifrages and some other house plants
runner
a stem that grows vertically below the surface of the ground; it typically has relatively long internodes
-Tubers produced at the tips of these in Irish potato plants
stolon
a swollen, fleshy underground stem
-Irish potato plants
tuber
an underground food-storage organ that is essentially a modified bud consisting of fleshy leaves that surround and are attached to a small stem
-Onions, lilies, hyacinths, and tulips
bulb
a vertically oriented, thickened food-storage stem that is usually enveloped by a few papery, nonfunctional leaves
-Crocus and gladiolus
corm
a flattened stem that resembles a leaf; aka phylloclade
-Stems of butcher’s broom plants, greenbriers, certain orchids, prickly pear cacti
cladophyll
a slender structure that coils on contact with a support of suitable diameter; it usually is a modified leaf or leaflet and aids the plant in climbing
tendril
What do humans use wood for?
fuel, shelter, weapons, and more
a portion of the base of a branch enclosed within wood
knot
a single season’s production of xylem (wood) by the vascular cambium
-Each year, a tree adds a layer of wood to its trunk
-During spring growth of wood, large-diameter water-conducting cells are formed (early (spring) wood); later in summer, the water-conducting cells produced have a smaller diameter (late (summer) wood)
annual ring
What is A?
apical bud (terminal bud)
What is B?
petiole
What is C and F?
node
What is D?
axillary bud
What is E?
internode
What is G?
stem
What is A?
apical bud (terminal bud)
What is B?
internode
What is C?
axillary bud (lateral bud)
What is D?
node
What is E?
leaf scar
What is F?
lenticel
What is G?
terminal bud scale scars
What is H?
petiole
What is I?
stipule
What is J?
stipule scar
How old is this Tilia stem?
3 years old
What is A?
leaf primordium
What is B?
protoderm
What is C?
apical meristem
What is D?
procambium
What is E?
leaf trace
What is F?
ground meristem
What is G?
node
What is H?
bud primordium
What is I?
leaf trace gap
What type of stem is this?
dicot
What type of stem is this?
monocot
How old is this tree?
7 years old
