vascular plant structure Flashcards
2 main clades of flowering plants
monocots and eudicots
monocots and eudicots are named for their number of
cotyledons: embryonic leaves in seed
monocots have ___ leaf veins
parallel
monocots are mostly …
Lillies and grasses
monocots: floral parts are in multiples of
3
eudicots have __ leaf veins
branched
eudicots: floral parts are in multiples of
4 or 5
parenchyma cells
*Thin and flexible walls
*Where plant metabolism occurs (photosynthesis)
collenchyma cells
*Living support cells
*Can lengthen if needed
*Often found in parts of the plant that are growing (stem/roots)
sclerenchyma cells
- Support cells, but they are often dead
- Cannot grow further
- They have thick walls that are strengthened with lignin protein
xylem cells transport
water
phloem cells transport
sugary sap
plant cells are organized into
tissues
plants are built as a series of layers called
tissue systems
tissue system layers:
dermal, vascular, and ground
dermal :
covers outside of plant
vascular:
forms the core of plant
ground:
between dermal and vascular
roots can be organized into
central taproot and spreading lateral roots
stems:
nodes where leaves attach
internodes:
between leaves
___ bud at end of stem
apical
___ buds near leaves
axillary
leaves: flat blade and stem like _____
petiole
stems + leaves =
shoot system
intermediate growth
no set full grown size
true for most plants
determinate growth
have a typical full grown size
true for most animals and many plants
primary plant growth
makes roots and shoots longer
secondary plant growth
makes roots and shoots thicker
meristems are required for
growth
plant stem cells:
-divide to produce…
-enable…
-found…
-new cells
-plant growth
-inside meristems
apical meristems
tips of roots and shoots
enables primary growth
lateral meristem
ring around stems and roots
enables secondary growth
intercalary meristem
in monocots only
continually grow leaves from base
root hairs
tiny extensions of root epidermis that increases surface area for absorption
most water is absorbed through…
root hairs
where are root hairs found
end of roots
internal structure of root: vascular cylinder location in center/middle…
*Larger xylem more central
*Smaller phloem are more outward
*Pericycle around vascular cylinder
internal structure of root: cortex
ground tissue between epidermis and vascular cylinder
endodermis:
inner layer of cortex
stores sugar
transports water and nutrients inward
primary root growth is created by
root apical meristem
primary root growth:
-meristem is protected by…
root cap
primary root growth:
meristem divides toward both ends of roots. cells elongate behind root tip, pushing the root through soil
lateral roots grow from
pericycle: layer surrounding vascular cylinder
lateral root growth is stimulated in
in soil with more nutrients
tap roots
- Deep root with lateral roots
- Allows access to water deep in the soil
- Common in eudicots
fibrous roots
- Many small roots
- Remove water from soil very quickly after rain
- Common in monocots
aerial roots
- Small plants grow on branches of larger plant and never reach soil
- Grow down from tree branches to soil
prop roots
- Branch to the side to provide additional support
- Important in loose soil or shallow root system
pneumatophores:
supply oxygen to deeper root tissues where there is no oxygen
o Roots need oxygen for cellular respiration
nodes
leaf, bud, or branch attachment
axillary buds
meristem in nodes
internodes
no leaves, buds, or branches
stem structure: vascular bundles
xylem and phloem
stem structure: Poth vs cortex ( ground tissue )
-poth: central of stem inside vascular tissue
-cortex: between vascular bundles and epidermis
dicot:
-vascular bundles in ___
- ____ inside, ___ outside
- ring
-xylem; phloem
monocot:
- ____ vascular bundles
-mixed …
-scattered
-mixed xylem and phloem in each bundle
primary shoot growth is created by
shoot apical meristem
apical dominance
- Apical bud reduces axillary bud growth
- Prevents side shoots near growing tip of shoot
primary shoot growth creates structures along stem:
leaves and axially meristems
primary shoot growth creates structures within stem
lateral meristems and primary xylem/phloem
secondary shoot growth is created by
lateral meristems
-2 kinds: vascular cambium and cork cambium
vascular cambium
*Divides inward to create _____
*Divides outward to create _____
*Seasonal changes form ______
-secondary xylem
-secondary phloem
-tree rings
cork cambium divides outward to create
cork
bark =
secondary phloem + cork
rhizomes and corms (stem modifications)
- Underground stems which can sprout new plants
- Have nodes and internodes
- Used for energy storage
rhizomes and corms: example
ginger
stolons and runners (stem modifications)
Run near soil surface to form new plants
tubers and bulbs (stem modifications)
- Underground stems modified for energy storage (Store energy as starch or sugar)
- Axillary buds can grow into new plants
- Bulbs have layers of leaves
tubers and bulbs example
potato
tendrils (stem modifications )
- Slender stems that wrap around structures
- Provide support for plant
- Usually seen in vines
thorns (stem modifications)
Modified branches that protect plant from being eaten by large herbivores
petiole
connects leaf to stem
blade/lamina
flat portion of leaf
vein
vascular tissue in leaf
veins contain
xylem and phloem
midrib
central vein (eudicots only)
margin
edge of leaf
venation pattern in monocots
- Parallel venation
- Veins DO NOT merge
venation pattern in dicots
- Net like venation
- Repeated branching pattern
- Often start from central vein
eudicot leaf types: simple
each leaf has one blade (no leaflets)
eudicot leaf types: compound
multiple blades
palmately compound
leaflets branch from one point
pinnately compound
leaflets ranch along central vein
doubly compound
leaflets branch along veins attached to central vein
cuticle (on surface)
- Waxy coating, not cells
- Reduces water loss
___ is under the cuticle
epidermis
stomata
- Openings for gas exchange
- Surrounded by guard cells
mesophyll
- Center of leaf
- Specialized for photosynthesis
leaf vein
- Xylem and phloem
stomata: gas exchange details
O2 exits leaf, CO2 enters leaf
transpiration
water evaporation out of leaf controlled by opening or closing stomata
guard cells
open or close stomata
what do pitcher plants, Venus fly traps, and sundew plants do?
- Capture animals, digest prey
