Root Lab Flashcards
what is the first organ to emerge from a seed?
root (radicle)
what are the three tissue systems of a root?
- dermal
- vascular (transport)
- ground (filler)
what three primary meristems make the tissue of roots?
- protoderm
- procambium
- ground meristem
what plant groups have taproot systems?
gymnosperms and dicots
what does a taproot consist of?
one major root with lateral branch roots
what plant group has a fibrous root system?
monocots
what does a fibrous root system consist of?
primary root dies off, formed of adventitious roots and their branches
what are the three regions of a root?
- zone of maturation
- zone of elongation
- zone of division
where are root hairs found?
zone of maturation
what are root hairs?
single, long cells that increase surface area for absorption by osmosis
what is the root cap?
protective bubble that prevents damage to the RAM
what are the 4 functions of roots?
- anchorage
- absorption
- storgae
- conduction
in which part of the root does the gravitropic response occurr?
in root cap
what causes the differences between intact and decapitated roots?
decapitated roots are depleted of starch
what are pneumatophores?
specialized roots for absorptio of air
what does the protostele root look like?
xylem in an X
what type of plants have protostele root arrangement?
dicots
what is the function of the cortex?
starch storage in plastids
what is the function of the endodermis?
regulates water and other substances entering root
what is the function of the pericycle?
keeps plant upright, site of new branch roots
what is the function of the pith?
transport and storage of nutrients
what does a eustele arrangement of root look like?
bundles of vascular tissue in ring (only monocots)
what does a siphonostele arrangement look like?
two rings of vascular tissue (only in monocots)
how are the roots of hydrophytes modified?
large air spaces called aerenchyma
what are epiphytes?
plants that grow on other plants for physical support
how are the roots of epiphytes modified?
not subterranean, but aerial, and some develop multi-layered epidermis called the velamen
how are the roots of parasitic plants modifed?
“haustoria” enter host tissue and take over vascualr system to steal nutrients
what are mycorrhizal roots?
roots that form symbiotic relatioship with fungus, which provies more nutrients
what replaces root hairs in mycorrhizal roots?
mycelia
