Plant Organ Structure/Function/Adaptation Chart
Plant Organ
Type
Roots
In monocots:
Structure
In dicots:
Modified roots
*adventitious roots Stems
Regular stem
Node Internode axillary bud apical bud -
Modified stem
Leaves
Monocots
Blade veins simple leaf compound leaf doubly compound leaf -
Dicots
Blade petiole veins also can be simple,
compound, doubly compound
Modified leaves
Function
Adaptation
Plant Organ Structure/Function Chart Answers
Plant Organ
Type
Structure
Function
Adaptation
Roots
Monocots: fibrous root
system
Mat of thin roots below soil
surface, no main root
Anchorage (to topsoil),
absorbs water and nutrients
(root hairs)
Doesn't grow deep, grows in
shallow soils with light rainfall,
hold topsoil in place and prevent
erosion
Dicots: taproot system
Vertical taproot with lateral
roots branching off sides
Anchorage, absorbs water and Grows deep into soil, can grow
nutrients (root hairs), stores
in soils where groundwater isn't
sugars and starches to be used close to the surface
during flowering
Modified roots
*adventitious roots develop from stems or
leaves instead of other
roots
Varied – strangling and prop
roots are aerial, buttress
shaped roots, pheumatophores
form spikes in the air
Support (prop roots and
buttress roots), storage
(beets), absorption
(pneumatophores)
Regular stem
Node – point where leaf is
To increase the plant's
attached
exposure to light
Internode – stem between
nodes
Axillary bud – structure that
can form a branch
Apical bud – end of a branch
with developing leaves, most
growth occurs at these
Stems
Modified stems:
Horizontal shoots (rhizomes Food storage (bulbs, tubers),
rhizomes, bulbs, stolons, and stolons), layers of
asexual reproduction (stolons)
tubers
enlarged bases of leaves
(bulb), irregular mass of
starch with clusters of axillary
buds (tuber)
Leaves
Monocots
Leaves (cont'd)
Each leaf is a blade, base of Mainly to perform
each blade forms a sheath that photosynthesis
Pneumatophores obtain oxygen
by growing above mud; buttress
and prop roots support trees and
plants so they can have the
advantage of growing tall
Apical dominance – inhibition of
axillary buds by an apical bud
increases plant's exposure to
light.
Example: an animal eats the end
of a shoot (apical bud)
stimulating growth of axillary
buds that are normally dormant
Similar to roots, food storage in
stems allows them to make
flowers and fruit later; asexual
reproduction allows a plant to
spread if conditions aren't right
for sexual reproduction
Many monocots are grasses with
long thin leaves, and few
envelops the stem; leaves
have parallel veins that run
length of blade
*can be...
Simple – one singe undivided
blade
Compound – blade consisting
of multiple leaflets
Doubly compound – each
leaflet in divided into smaller
leaflets
monocots grow as large as dicots.
The evolutionary advantage of
smaller plants with thinner leaves
is that they don't need to use as
many resources to grow large.
Dicots
Blade attaches to the petiole Mainly to perform
(a stalk) which attaches to the photosynthesis
stem at a node; have a
branched network of veins
*can be simple, compound, or
doubly compound
Large leaves are better able to
withstand strong winds if they're
compound. Having compound
leaves helps confine pathogens to
one leaflet instead of whole leaf
Modified leaves
Tendrils, spines, thick fleshy
leaves
Small surface area of spines
reduces water loss in hot and dry
climates; succulents' fleshy
leaves store CO2 gathered at
night and close stomata during
the day to reduce transpiration;
bracts are large colored leaves
that surround smaller flowers to
attract pollinators instead of
petals (poinsettias)
Support (tendrils), protection
and less water loss (spines),
storage (thick fleshy leaves of
succulent plants),
reproduction (succulent
leaves, bracts)