Please enable JavaScript.
Coggle requires JavaScript to display documents.
Ch:8 Roots - Coggle Diagram
Ch:8 Roots
Other types of roots and root modification
Storage roots
long term storage for carbohydrate
produces new shoots in spring
For ex: beets, carrots celery etc.
Prop Roots
produces adventitious roots
often 20-50 cm long
some of the prop roots generate buttress roots
For ex: Ficus, banyan trees etc.
Aerial Roots
roots spread along the surface of barks
velaman acts as water proof barrier
For ex: roots of orchids.
Mycorrhizae
seed plant species has this root.
symbiotic relationship with soil fungi
Contractile roots
uppermost portions slowly contract
contraction is caused by change in shape of cortex cells.
For ex:
Oxalis, Gladiolus, Crinum
Root Nodules and NItrogen Fixation
nitrogen fixation: atmospheric nitrogen conversion into usable form
root nodule is formed by mitotic division.
may be simple or complex.
Haustorial Roots of Parasitic Flowering Plant
haustoria: parasitic plant roots highly modified.
must adhere firmly to host plant.
Roots of Strangler figs
roots clings to the bark of strangler figs.
Internal Structures of roots
Root Cap
small and meristematic
when pushed towards the edge, structure and metabolism change dramatically
constantly regenerating
Root Apical Meristem
more orderly than shoots
has quiescent center
Zone of elongation
occurs behind the root apical meristem
cells differentiate in visible pattern
has ground tissue
tissues are permeable
Zone of Mauration
root hairs grow
zone of elongation merges
has endodermis
casparian strips
metaxylem and metaphloem becomes differentiated fully
Mature portions of the roots
Passage cells
Has casparian strips
root pressure
Organization of root system
highly branched
taproots developed from radicle
largest root system
Lateral roots can swell like tap root
monocots and dicots has fibrous roots
Individual structure of roots
root tip: growth in length occurs
root cap protects root apical meristem
mucigel: lubricates the passage into the soil
Zone of elongation: behind root cap and root apical meristem
root hair zone
has narrow trichomes
Functions
Anchoring
absorption of water and minerals
producing hormones
