Chapter 35: Vascular plant structure, growth and dev Flashcards
Levels of plant organization
cells, tissues, organs
organs
organization of tissues to perform function; reflects adaptations to draw nutrients
root system functions
anchor, absorb, store
root morphologies
taproot, fibrous root
root hair
increase surface area for absorption
adventitious roots
root tissue emanating from stems or leaves
function of shoots
reproduction and photosynthesis
primary growth
upward growth via apical bud
branch growth
formed by axillary buds
meristem cells
perpetually embryonic cells that are in apical and axillary buds
apical dominance
axillary bud growth inhibited by proximity of apical bud
rhizomes
modified stems; grow horizontally underground
stolons
modified stems; grow horizontally above ground
leaf purpose
main organ for photosynthesis; intercept light, exchange gases/heat; defend
leaf elements
blade and petiole
simple v. compound leaf
defined by axillary bud; compound leaf has many leaflets per axillary bud
tissue types
dermal, vascular, ground
dermal tissue system
external protective covering
herbaceous plant dermal tissue
epidermis with waxy cuticle
woody plant dermal tissue
periderm
vascular tissue system
internal transport between shoot and root systems
stele
arrangement of xylem and phloem
ground tissue system
tissues that are neither dermal nor vascular
cortex
between dermal and vascular tissue
pith
within vascular tissue
parenchyma cells
thin primary walls; synthesize and store organic products. Can differentiate into other cells
collenchyma cells
unevenly thickened primary walls; living support cells. Often around vascular cells
sclerenchyma cells
rigid support cells; dead and made of hard lignin
xylem cells
water conducting cells; lignified, dead support cells
tracheids
long, narrow cells connected by ‘pits’
vessels
shorter, wider cells; aligned into vessels separated by perforation plates
phloem cells
sugar conducting, living cells
sieve cells
long, narrow cells in seedless vascular plants and gymnosperms
sieve tubes
sieve cells in angiosperms; more complex
sieve plates
connect sieve tube elements
companion cells
connected via plasmodesmata to sieve tube; provides nucleus that functions for both cells
primary growth root structure
apical meristem located behind root cap
zone of cell division
meristem and immediate derivatives
zone of elongation
cells elongate, pushing root tip forward
zone of differentiation
cells mature to specialized cell types
pericycle
outermost layer of cells in stele
lateral roots
originate from the pericycle; keeps vascular cylinders continuous
apical bud meristem
shoot tip, surrounded by lear primordia
axillary bud meristem
areas of meristem left behind by leaf primordia
lateral stems
arise from axillary bud meristems
secondary growth
caused by lateral meristems; horizontal growth in part of plant no longer undergoing primary growth
periderm
outer layer of bark
vascular cambium
cylinder of meristematic initials between xylem/pith and phloem/cortex
cork cambium
2nd lateral meristem in the outer cortex of stems; generates cork cells, replaced by periderm
bark
periderm and secondary phloem
growth
cells elongate and divide
morphogenesis
specific tissue and organs develop at specific places
differentiation
cells change to specific specialized types
polarity
position information; root to shoot axis
position
position information relative to other cells
