Plant Tissues Flashcards
3 (4) major organs
Root
Stem
Leaves
Flowers (in angiosperms)
2 major organs based on function
Vegetative
Reproductive
2 systems
Roots
Shoot
Derived from Apical meristem
Made of Primary tissues
Herbaceous part of plant
Only plant body of herbs
Primary Plant Body
Derived from lateral meristems
Made of secondary tissues
Constitutes wood and bark of plant
Woody plants have primary tissues that differentiate into secondary tissues
Secondary Plant Body
Thin and flexible primary cell walls
most common type of plant cell
constitutes to all soft parts of herbaceous parts of plant
Parenchyma
Type of parenchyma:
Tightly packed parenchyma cells
pith parenchyma
Type of parenchyma:
presence of numeral starch grains
cortical parenchyma
Type of parenchyma:
has chloroplasts that are red stained
chlorenchyma
Type of parenchyma:
parenchyma Used for storage
storage parenchyma
Type of parenchyma:
Help in gas exchange between shoot and root found in aquatic plants
Arenchyma
contain wax and oil that cover epidermis
made of cutin,cutan and epiticular wax
aerial portions of plant; none in roots
Epidermal Parenchyma: Cuticular Membrane
Functions:
prevent dessication
inhibit pathogen invasion
blocks certain wavelengths of UV Radiation
Lack chlorophyl; make up majority of epidermis
tightly packed
found in leaf and stem surfaces
Epidermal Parenchyma: Pavement Cells
Under epidermis
Epidermal Parenchyma: Hypodermis
Has guard cells with stomata that change shape when swollen
has chloroplast
sensitive to light, humidity, time of day, and plant hormone ABA
Epidermal Parenchyma: Stomatal Pore complex
Location of stomata in plant
Epistomatic; adaxial
Hypostomatic; abaxial
Amphistomatic; both
Single subsidiary cell surrounds guard cell
Floating guard cells
2 subsidiary cells border along parallel axes of guard cells
Paracytic
2 subsidiary cells border right angle to axes of guard cells
Diacytic
3 subsidiary cells adjoin the guard cells
triacytic
3 subsidiary cells adjoin but one is smaller than the other 2
anisocytic
4 subsidiary cells adjoin the guard cells
tetracytic
Subsidiary cells are indistinct from pavement cells
anomocytic
dumbbell shaped subsidiary cells parallel in paracytic fashion found in grass family
Graminaceous
Distribution of stomata
Random
clustered
linear
sunken
extensions from epidermis; protect from biotic and abiotic stresses
Trichomes
functions:
raises humidity of air in leaf surfaces
reduce light entering leaf; scattering irradiation
Physical and chemical barriers against herbivory
reduce evapotranspiration and water loss
Forms of trichomes
unicellular and unbranced
unicellular and branched
multicellular and unbranched
unicellular and branched
glandular
stinging hair
Type of trichome:
Short and round and produces chemical to repel insects
Glandular
Type of Trichome:
short and stiff
inject component in animals as protection
Stinging hair
example: Uritcaceae
unevenly thickened primary walls that exhibit plasticity
support young parts of plant shoot
at maturity can provide support withoyut restraining growth
derived from parenchyma
Collenchyma
Type of collenchyma:
Greatest wall thickenings where cells meet at the corners
Angular collenchyma
Type of collenchyma:
Thickened portions of cell wall like bricks
Lamellar collenchyma
Type of collenchyma:
presence of intercellular space especially in angles
Lacunar Collenchyma
Type of collenchyma:
evenly distributed primary wall thickenings with little to no intercellular spaces
Annular collenchyma
Primary and secondary wall always lignified
more rigid and support plant by strength alone
dead but functional and mostly composed of secondary cell wall
sclerenchyma
Type of sclerenchyma:
very narrow; long
support xylem cells in secondary growth; phloem in primary growth
found in clusters; adaxial and abaxial
differentiation from parenchyma to sclerenchyma
Fibers
Type of sclerenchyma:
found in seed, fruit, and leaf
development related to hormonal signals in wounded plants
Sclereids
Type of sclereid:
strong for support and lignin is present
leaf scar and process of sclerification
Brachysclereids
Type of sclereid:
star shaped and supports leaves
calcium oxolate in cell wall helps its shape
astrosclereids
Type of sclereid:
outer and inner layer that protects seed
macrosclereids and osteosclereids
Type of sclerenchyma:
allow water flow in plants
Tracheary elements
Exhibits determinate growth
animal growth
exhibits indeterminate growth
plant growth
divide indefinitely
has apical (SAM and RAM)
has lateral (Cambium)
has intercalary (Grass; stem and leaf sheaths)
Undifferentiated
active in cell division
Meristems
Type of Meristem:
primary growth; Root extension in soil
shoot increase exposure to light
make up most of herbaceous parts of plants
apical meristem
Type of meristem:
vascular cambium and secondary xylem where thickening happens
cork cambium replaces epidermis with stronger periderm
Lateral meristem
Types of primary tissues
protederm
ground meristem
procambium
Type of protoderm:
outermost layer
contain cutin and forms waxy and oily cuticle
contain stomata and trichomes
Epidermis
functions:
prevent water loss
barrier against invasion
shield internal cells
prevents overheating
In epidermis:
open in day; close at night
swell by absorbing water; shrink by losing water
entry of gases; prevent water loss
stomata
in epidermis:
block incoming sunlight
deter herbivory
conserve moisture in leaves
some die at maturity but become secretory glands
trichomes
Type of ground meristem:
interior to epidermis
contain homogenous photosynthetic parenchyma
also aerenchyma
cortex
Type of procambium:
xylem
phloem
vascular bundle
Vascular tissues
type of vascular tissue:
conducts water and minerals
dead but functional at maturity
has tracheary elements
parenchyma to sclerechyma (lignified)
secondary cell wall organized to be annular thickennings
xylem
Type of xylem:
long and thin - water moves cell to cell through pits
tracheids
type of xylem:
wide and short and forms vessels
vessel elements
Type of vascular tissues:
alive and functional at maturity
distributes sugars and minerals
has sieve elements
Phloem
Type of phloem:
elongated and spindle shaped
found in non-angiosperms
distributed over all its surfaces
sieve cells
type of phloem:
large sieve pores
found in angiosperms
aligned at sieve plate
sieve tube members
Type of sieve tube members:
found at sides
immature parenchymatous sievec elements
enlrage plasmodesmata diamater
clusters called sieve areas
sieve pores
Type of sieve tube member:
found up and down
sieve plate
Type of vascular tissue:
has xylem and phloem
angiosperms form ring surrounding pith
monocots are scattered
vascular bundle
