ROOTS elevated-tree-roots-in-park-591408977-5a7a3f10642dca0037034fb9 …
most roots have 3 functions
absorbing the water and minerals
anchoring the plant firmly to a substrate
External structure of roots
Organization of root system
increase absorption and transport capacities of the root system
small numerous roots
coming out to the tap root.
Fibrous root system.
monocots and eudicots mass of similar sized roots.
structure of individual roots.
cells closest to root meristem also called merisistematic.
undergo cell division.
cells on edge grow toward side and proliferate.
provide effective protection.
helps remain in place.
cells structure and metabolism chance dramatically.
middle lameila breakdown and releases cells.
Dictyosomes of root cap cells secret complex ploysaccharide.
cells undergo division and expansion.
Zone of elongation
cells differentiate into visible pattern.
just behind root apical meristem
regions where cells expand greatly.
protoxylem and protophloem closest to meristem.
older larger cells develop to meistem.
ground tissue differentiate into root cortex.
Root hair zone.
Epidermal cells extend out as narrow trichomes.
forms only in a part of the root that is not enlogating.
Increase surface area.
form carbonic acid and is unicellular
no thick walls.
Zone of maturation/Root hair zone
innermost layer of cortical cells
root hair increase surface area.
root hair grows.
control types of materials that enter the xylem
Root apical meristem.
Usually cells originate here.
mitotically inactive cells is known as
root apical meristem destroyed
take over by
Zone of Elongation
outermost cells are protioderm.
differentiate into epidermis.
center is provascular tissue.
Develop in primary xylem and primary phloem.
as in them stem
protoxylem and protophloem.
larger cell develop into metaxylem and metaphloem.
tissues are quite permeable.
Zone is short
little absorption occurs.
Mature portions of the root.
slow to develop.
absorption of minerals.
cause powerful absorption of water and water pressure called
Other type of root and root modifications.
Storage Roots. :black_flag:
have stable envrionment.
long term storage for Co2
use stored Co2 to produce new shoot.
annual plant can survive without storage.
Prop Roots :check:
transport additional water and nutrients.
prop root acts as stabilizers.
can produce massive trees.
Aerial roots of orchids. :red_flag:
velaman acts as a waterproof trees.
Orchids live attached to the branches of trees.
roots dangle freely in the air.
velamen = root epidermis.
important in keeping stems at proper depth.
undergo much contraction.
shoot at soil level or deeper.
Symbiotic relation with soil fungi
woody forest plant
Roots nodule and nitrogen fixation.
swollen and occupied by bacteria.
nitrogen fixation chemical conversion pf atmospheric oxygen.
infection thread hold bacteria.
Haustorial Roots of parasitic Flowering plants.
roots of parasitic plants.
root like structure remains.
firmly adhere to host.
inadequate for growth in soil.
Origin and development of lateral woods. :checkered_flag:
Lateral root initated by cell division in pericycle.
small root pordium.
roots swells into the cortex.
epidermis may be torn or crushed or may undergo cell division.
new lateral roots destroy cells of the cortex and epidermis.
ultimately breaking endodermis.
small cells at base of root.
cells close to edge of cap=change dramatically.
provide protection for root apical meristem.
root hair die after copule of days.