plant anatomy Flashcards
meristems
Clumps of small cells with dense cytoplasm and large nuclei (highly mitotic)
apical meristems
elongate the plant, give rise to three types of tissue, cause primary growth
lateral meristems
increase thickness of plant, add new vascular tissue, cause secondary growth
dermal tissue
for protection (skin and bark)
ground tissue
for storage, photosynthesis, secretion
vascular tissue
for conduction
xylem
part of vascular tissue, transports water and dissolved minerals, dead cells at maturity
phloem
part of vascular tissue, transports nutrients
node
point of attachment of leaf to stem
internode
area of stem between two nodes
axillary buds
develops into branches with leaves or may form flowers
apical buds
extends the shoot system during growing season
parenchyma cells
part of ground tissue
responsible for storage, photosynthesis, and secretion
collenchyma cells
uneven cell walls, provide flexible support for plant organs
sclerenchyma cells
thick secondary cell walls, usually dead at maturity
fibers
type of sclerenchyma cells
long and slender strands
sclereids
type of sclerenchyma cells
variable shape, branched
trichomes
produce oil
hairlike structures
increase solar reflectance
defend leaves against predation
cells of xylem
tracheids: taper and overlap
vessels: continuous tubes of short/wide cylindrical cells
cells of phloem
sieve tube members: living cells separated by sieve plates, lack most organelles
companion cells: metabolic support from sieve tube members, have ribosomes and mitochondria
stem organization
epidermis on outside
ground tissue throughout
vascular tissue bundles (phloem –> outside, xylem –> central)
vascular cambium (lateral meristem)
forms secondary xylem and phloem, xylem layer forms annual ring
cork cambium (lateral meristem)
produces periderm of bark and other tissue to protect stem/trunk, produces lenticels to allow in oxygen
tendrils
slender, twining strands that enable plant to seek support by climbing other surfaces
thorns
modified branches appearing as sharp outgrowths that protect plant
rhizome
stem that grows horizontally underground
corm
stem that grows horizontally underground, rounded and fleshy
runner and stolon
stem runs parallel to the ground/just below the surface and give rise to new plants
tuber
stem that stores starch
bulb
functions as underground storage unit
tap root
main root that grows down vertically and has many smaller lateral roots
fibrous root system
located closer to soil surface and forms dense network of roots
lamina
flattened blade of leaf
petiole
stalk of leaf
venation
pattern of veins in a leaf
phyllotaxy
arrangement of leaves on a stem
simple leaf
blade is either completely undivided or lobed
compound leaf
blade is completely divided, forming leaflets
palmately (compound leaf)
leaflets radiating outwards from one point
pinnately (compound leaf)
feather like, leaflets arranged along midrib
mesophyll
parenchyma cells between upper and lower epidermis
palisade mesophyll
two rows of tightly packed cells
spongey mesophyll
loosely arranged cells with air spaces
type of leaf arrangement
alternate, opposite, whorled
monocot seed
one cotyledon
eudicot seed
two cotyledon
monocot flowers
parts in 3’s
eudicot flowers
parts in 4’s or 5’s
monocot leaves
parallel veins
eudicot leaves
reticulated veins
monocot shoots
dispersed paired bundles of xylem and phloem
eudicot shoots
paired bundles of xylem and phloem on perimeter
monocot roots
paired bundles of xylem and phloem on perimeter + casparian strip
eudicot roots
central “star” of xylem with alternating phloem + casparian strip