Title: Plant Organization:
1Plant Organization Leaf development
2Organization
- Organization in plants is dependent upon
programmed, controlled cell division, followed by
growth, further cell division and ultimately,
differentiation. - Programmed and controlled cell division occurs
within the domain of the vegetative apex. - Leaves also follow a programmed development
process
3the apex
All the tissues within the apex differentiate
rapidly. By about 150 µm, cells within the apical
region are starting to differentiate. In the pine
apex (above), you can see developing leaflets.
The Coleus apex to the right, shows rapidly
developing leaflets beneath the apical dome.
4internal organization
adaxial epidermis
palisade mesophyll
vascular bundles
spongy mesophyll
stomata
5leaf development
these form the epidermis and associated structures
marginal
two types of initials
submarginal
these form mesophyll as well as the procambial
and cambial tissue
6how organized?
epidermal, mesophyll and vascular tissues are
organized and develop in specific ways. What is
the control mechanism?
7structural functional tissue
dermal
non- vascular
vascular
dermal
8two meristems
marginal
sub marginal
9deriving procambium
marginal
sub marginal
procambium
10Esaus developmental outline
upper epidermis
palisade parenchyma
bundle sheath
Vascular bundles
procambium
MI
SI
bundle sheath
middle spongy parenchyma
lower spongy parenchyma
lower epidermis
see notes below
11no middle spongy layer?
upper epidermis
palisade parenchyma
bundle sheath
procambium
vascular bundles
MI
SI
bundle sheath
lower spongy parenchyma
lower epidermis
12add a mestome sheath
upper epidermis
palisade parenchyma
bundle sheath
mestome sheath
MI
SI
procambium
vascular bundles
mestome sheath
bundle sheath
lower spongy parenchyma
Notes
lower epidermis