STEM STRUCTURE AND TRANSPORT Flashcards
these link a plant’s roots to its leaves
STEMS
stems can be _________, with soft tissues; or _____, with extensive hard tissues of wood and bark
herbaceous;
woody
stems perform three main functions:
- structural support
- internal transport
- production of new living tissue (buds)
stems of some species are modified for _________ reproduction
asexual
type of stem growth that occurs at apical meristems at root tips, shoots, and within buds of stems
PRIMARY GROWTH
type of stem growth that occurs at lateral meristems of stems and roots
SECONDARY GROWTH
vascular bundles are arranged in a circle in cross section
herbaceous eudicot stems or monocot stems?
HERBACEOUS EUDICOT STEMS
the protective epidermis is covered by a waxy cuticle; stomata permit gas exchange
(herbaceous eudicot stems or monocot stems?)
HERBACEOUS EUDICOT STEMS
an inner cylinder of ground tissue may contain parenchyma for photosynthesis, and collenchyma and sclerenchyma for strength and structural support
(herbaceous eudicot stems or monocot stems?)
HERBACEOUS EUDICOT STEMS
xylem is found on inner side of the vascular bundle, and phloem toward the outside
(herbaceous eudicot stems or monocot stems?)
HERBACEOUS EUDICOT STEMS
in herbaceous eudicot stems, xylem is found on _______ of the vascular bundle, and phloem toward the _________
inner side; outside
in some herbaceous eudicot stems, phloem has a _______ that helps strengthen the stem
phloem fiber cap
some stems have a single layer of vascular cambium cells between xylem and phloem
(herbaceous eudicot stems or monocot stems?)
HERBACEOUS EUDICOT STEMS
the pith is located at the center of the stem and functions primarily in storage
(herbaceous eudicot stems or monocot stems?)
HERBACEOUS EUDICOT STEMS
vascular bundles are scattered throughout the stem, each vascular bundle is enclosed in a bundle sheath of sclerenchyma cells
(herbaceous eudicot stems or monocot stems?)
MONOCOT STEMS
no distinct areas of cortex and pith – ground tissue around the vascular tissues performs the functions of cortex and pith
(herbaceous eudicot stems or monocot stems?)
MONOCOT STEMS
no lateral meristems and no secondary growth because of the lack of vascular cambium
(herbaceous eudicot stems or monocot stems?)
MONOCOT STEMS
in monocot stems, , each vascular bundle is enclosed in a what
bundle sheath of sclerenchyma cells
a part of stem that forms layers of cells that constitute cork
cortex
a part of stem that is composed of soft, spongy parenchyma cells, which store and transport nutrients throughout the plant
pith
________ undergo secondary growth due to the activity of vascular cambium and cork cambium
woody eudicots
cells of vascular cambium divide and produce _____________ to replace the primary xylem and _____________ to replace the primary phloem
secondary xylem (wood); secondary phloem (inner bark);
cells of cork cambium divide and produce ________ and _________, which replaces the epidermis
cork cells and cork parenchyma
a thin layer of cells between xylem and phloem in vascular bundles that becomes continuous when production of secondary tissues begins
VASCULAR CAMBIUM
cells in vascular cambium divide in two directions:
cells formed inside become secondary xylem (wood);
cells formed outside become secondary phloem (inner bark)
these secondary tissues transport water, minerals, and sugar vertically throughout the woody plant body
secondary xylem and secondary phloem
lateral movement occurs through ____ – chains of parenchyma cells that radiate from the center of the woody stem or root
RAYS
cork cells (formed outside cork cambium) are ____ at maturity, have ________ walls and ______ the stem
dead; waterproof; protect
cork parenchyma cells (formed inside cambium) store __________
water and starch granules
stomata are replaced by __________, which permit gas exchange through the periderm
LENTICELS
woody twigs have ____________ (buds)
EMBRYONIC SHOOTS
two kinds of embryonic shoots in woody twigs
TERMINAL BUD
AXILLARY (LATERAL) BUDS
differentiate terminal buds from axillary (lateral) buds
terminal buds are located at the tip of the stem, protected by bud scales
axillary (lateral) buds are located in the axils of a plant’s leaves
a location on a plant stem which is the angle between the leaf and the upper part of the stem
AXILS
when terminal and axillary buds grow, they form _______ that bear leaves and/or flowers
branches
during winter dormancy, _______ cover the terminal bud and protect the delicate apical meristem
BUD SCALES
when do bud scales fall off, leaving bud scale scars
each spring, when the bud resumes growth
when do bud scales cover the terminal bud and protect the delicate apical meristem
during winter dormancy
shows where each leaf was attached on the stem
LEAF SCAR
within a leaf scar, the vascular tissue to the leaf forms ________
bundle scars
the difference between summerwood of one year and springwood of the following year gives the appearance of ________
ANNUAL RINGS
the age of a woody stem in ________ zones can be determined by counting the annual rings
temperate
annual rings are not a reliable method of determining ages of ________ trees
tropical
