PLANT ROOTS Flashcards
4 functions of roots
anchoring the plant
absorbing water and minerals
producing hormones
Fleshy taproots are the plant’s main site of carbohydrate storage during winter.
2 hormones produced by roots
cytokinin and gibberellin
monocot roots
fibrous root system
eudicot roots
tap root system
roots grow from
apical meristem
apical meristem is protected by
root cap
behind the root cap and apical meristem
where cells undergo division and expansion
zone of elongation
region in which many of the epidermal cells extend out as narrow trichomes
root hair zone
maturing cells detect gravity using
starch grains
the cekks dictyosomes in the root caps secrete
mucigel
a mitotically inactive central region which can replace the apical meristem if it becomes damaged
quiescent center
here, cells are enlarging, nuclei become less distinct
protoderm, provasc. tissue, and ground tissue begin to differentiate, no cells are mature yet.
zone of elongation
marked by the production of root hairs growing outward
increases absorption of water and minerals.
tissues are differentiated here.
zone of maturation / root hair zone
these cells transfer minerals from the epidermis to the vascular tissue
cortex cells
the innermost layer of cortical cells differentiates into a cylinder called the -
ENDODERMIS
the radical walls of the endodermis are encrusted with
waterproof lignin and suberin (casparian strip)
involved in controlling the minerals that enter the xylem and phloem
casparian strip
Minerals can cross the endodermis only if?
endodermal protoplasts absorb them.
A cylinder of tissue, interior to the cortex, forms the ____
it consists of both xylem and phloem in the center.
stele
an irregular region of parenchyma cells between the vascular tissue and the endodermis
where lateral roots are produced
pericycle
difference between monocot and dicot roots
pith is present in monocot
eudicot - star shaped VB
Endodermal cells that are slow to mature and have only the Casparian strip are called
passage cells
what happens when root hairs die
Shortly after the root hairs die, underlying cortex and epidermis often die. − They are shed from the root.
