mod 4 lec Flashcards
what are the 4 functions of roots
absorbs
stores
anchors
produce hormones
elongation in response to stimuli
auxins
seed germination
gibberellins
cell division
growth of fruits
cytokinin
maturation and aging
ethylene
death of leaves
abscisic acid
root growth of dicots and gymnosperms
taproot system
root growths of monocot and seedless vascular plants
fibrous root system
composed of thimble-shaped mass of parenchyma cells covering the tip of each root.
protects delicate tissues behind from damage as the young root tip pushes through the soil particles
root cap
what does the root cap contain
amyloplast
dictiosomes
acts as gravity sensors and orients the root to grow downward
amyloplast
this region is composed of apical meristem and produce the root cap
region of cell division
what are the three subdivision of apical meristem
protoderm
ground meristem
procambium
this region merges with apical meristem, cells become longer and wider
region of cell elongation
this region is also known as differentiation or root hair zone..
cells mature or differentiate to form into the dermal, vascular and ground tissues
region of maturation
tubular extensions of specialized epidermal cells that absorbs water and minerals and adheres tightly into soil particles for anchorage
root hairs
parenchyma cells resting between the epidermis and the inner tissues that acts as the food storage
cortex
single-layered cylinder of compactly arranged cells whose primary walls are impregnated by suberin
endodermis
suberin band which prevents water from passing through the permeable cell walls of the endodermis
casparian strip
thin-walled endodermal cells which serves as the passageway of materials between the cortex and the vascular bundle
passage cells
a collective core of tissues that lies inside the endodermis which may conduct water or food in solution
vascular cylinder
region where lateral roots arise in which their cells continue to divide even after maturtion
pericycle
four functions of stems
transport
store
supports
produce new living tissues
grows stems that bear leaves and flowers located at the tip of the stem
terminal bud
protects dormant terminal buds
bud scales
left after bud scales fall off
bud scars
also known as lateral buds. grows stems that bear leaves and flowers found in the axils
axillary bud
shows where the leaf WAS attached to the stem
leaf scars
area of the stem where the leaves are attached
node
area on the stem between two successive nodes
internode
site of loosely arranged cells that allows gas exchange
lenticel
outer covering that provides protection by producing cuticle
epidermis
central cylinder of the stem which is composed of vascular bundle
stele
vascular cells arranged in a circular pattern
vascular bundle
ground tissue composed of large, thin-walled parenchyma cells that functions primarily for storage
pith
main growth tissue of stems and roots
vascular cambium
functioning secondary xylem
sapwood
non-functioning secondary xylem which provide structural support
heartwood
continuous cylinder or dividing cells that makes up the periderm
cork cambium
are dead at maturity and have heavily suberized or waterproof walls
cork cells
stores water and food
cork parenchyma
functions of leaves
identity
produce food
a part of the leaves that is broad, flat portion of the leaf
lamina/blade
a part of the leaves where the stalk is attaches the leaf to the stem
PETIOLE
a part of the leaves where there is a leaf-like outgrowth at the base of the petiole
stipule
a part of the leaves where there is no stipule
sessile
a type of leaf with only a single plate
simple
a type of leaf with two or more divided leaflets
compound
leaflets are borne on an axis that is a continuation of the petiole
pinnately
leaflets arise from common point at the end of the petiole
palmately
one leaf at each node
alternate
two leaves at each node
opposite
three or more leaves at each node
whorled
primary veins run approximately parallel to one another along the leaf’s long axis with smaller veins forming connections between the primary veins
parallel
smaller veins branch off the larger veins that resembles a net
reticulated / netted
