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MORPHOLOGY OF FLOWERING PLANTS. ROOTS. Direct elongation of radicle. Grows inside the soil Bears lateral roots. TYPE OF ROOTS. FUNCTION OF ROOTS. Absorb water & Minerals. Anchorage Store reserve food Synthesis of hormone. STILT ROOT. LEAF CHARACTERISTICS. It is lateral & flat.
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ROOTS • Direct elongation of radicle. • Grows inside the soil • Bears lateral roots.
FUNCTION OF ROOTS • Absorb water & Minerals. • Anchorage • Store reserve food • Synthesis of hormone
LEAF CHARACTERISTICS • It is lateral & flat. • Borne at the stem at the node. • Bears a bud at its axile which later develops into a branch.
TYPES OF LEAVES • Simple-lamina is entire or if incised,incision does not touch mid rib. • Compound-incision of lamina reach up to the mid rib breaking it into number of leaflets. • Pinnately compound-leaflets are present on a common axis called rachis . • Palmately compound-leaf lets are attached at a common point I;e tip of petiole.
PHYLLOTAXY(arrangement of leaves on stem) • Alternate-a single leaf arise at each node. • Opposite- a pair of leaves arise at each node. • Whorled-more than two leaves arise at a node 7 form a whorl.
Leaf Modifications • There are 2 basic types of root modifications: • spines • Tendrils • Phyllode • pitchers
Leaf tendrils • They are specialized for providing support. • They form spring like structure when they come in contact with any substrate and coil around them to provide anchorage.
Pitchers • They are specialized for providing nourishment in the nitrogen deficit areas. • They form pitchers and store proteolytic enzymes in the fluid secreted in the lumen of pitcher for digestion of insects
Phyllode • They are specialized for reducing the rate of transpiration. • In these structure the rachis look like leaf or petiole modifies to form leaf like structure while leaf lamina is highly reduced
ASSIGNMENT:- • Distinguish between Parallel and reticulate venation. Alternate and whorled phyllotaxy. Pinnately compound and palmately compound leaf. 2. Define phyllotaxy. 3. Mention any two plants showing opposite phyllotaxy. • Write short note on the modification of leaves in plants.
INFLORESCENCE(arrangement of leaves on floral axis) • Racemose-main axis continues to grow,flowers are arranged laterally in an acropital manner. • Cymose-main axis terminates in a flower having limited growth,flowers are borne in a basipetal manner.
CHARCTERSTICS OF FLOWER • Bisexual/unisexual • Actinomorphic/zygomorphic/asymmetric • Trimerous/ tetramerous/ pentamerous • Bracteate/ ebracteate • Hypogynous/perigynous/epigynous • Superior and inferior ovary.