LEAVES Flashcards
flat, thin green, appendages to the stem,
contain-ing supporting and conducting strands in their structure.
Leaves
A typical angiospermic leaf consists of the following parts:
Leaf base or hypopodium
Petiole
Lamina or Leaf blade
Stipules
By means of which it is attached to the stem.
Leaf base or hypopodium
It is the stalk of leaf with which leaf blade is
attached to the stem
Petiole
The flat expanded part of the leaf is lamina or leaf blade (Epipodium).
Lamina or Leaf blade
These are the two small outgrowths found at the base of the leaf, to protect the axillary bud. Leaves may or may not have stipules.
Stipules
Some stipules perform special functions and hence are put into following types:
Tendrillar stipule
Foliaceous stipules
Bud stipules
Spiny stipules
The stipules get modified into coiled, tendrils helping the plant to climb, i.e. Indian sarsaparilla (Smilax microphylla).
Tendrillar stipules
In case of plants with compound leaves some of the leaflets get converted into
Foliaceous stipules
Scaly stipules of the Ficus sp. are charac-teristic, which protect the terminal vegetative bud.
Bud stipules
In some plants, the stipules get converted into spines and help against browsing animals as in the case of Acacia and Zizyphus
Spiny stipules
There are five types of stipules which are as under:
Free lateral
Adnate
Inter-petiolar
Axillary
Ochreate stipules
Shape of the lamina of leaves
Acicular
Subulate
Linear
Oblong
Ovate
Obvate
Obcordate
Spathulate
Cuneate
Cordate
Sagittate
Hastate
Lyrate
Runcinate
Rotund
Elliptical or oval
Peltate
