Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 5: Tissues and the Primary Growth of Stems (External Organization…
Chapter 5: Tissues and the Primary Growth of Stems
Internal organizations of Stems: Arrangement of Primary Tissues
epidermis
outermost surface of an herbaceous stem
chemical
cutin
waxes
properties
waterproofing
ingested by
fungi
bacteria
animals
cortex
interior of the epidermis
vascular tissues
two types
pholem
distributes
sugar
minerals
xylem
conducts
minerals
water
vascular bundles
xylem and phloem work together
Basic Types of Cells and Tissues
sclerenchyma
lots are dead at maturity
primary walls
elastic support
secondary walls
involved in water transport
fibers
long
those alive involved in storage
many dead
sclereids
dead when mature
isodiametric
parenchyma
collenchyma
uneven thick walls
provides plastic support
alive at maturity
Stem Growth and Differentiation
apical meristems
cells divide by
cytokinesis
mitosis
subapical meristems
just below apical meristem
cells are
dividing
growing
External Organization of Stems
leaf axil
where leaf attaches
stem
nodes
where leaves are attached
bud scales
protect inside organs
modified scales
internodes
region between nodes
phyllotaxy
important positioning of leaves
decussate
leaves located in four rows
whorled
three or more leaves per node
opposite
leaves two per node
spiral
leaves not aligned with their nearest neighbors
alternate
leaves per node
distichous
leaves located in two rows only
auxiliary bud
young leaves
rhizomes
allow plants to spread underground
examples
bamboo
canna lilies
irises
fleshy horizontal stems
terminal bud
extreme tip of each stem
tubers
horizontal
only grow for short periods
example
potatoes
