Primexein

1. 1

2. • POLLEN WALL
• LAYERS OF POLLAN
• INTINE
• EXINE
• DEVELOPMENT OF POLLEN WALL
• EXINE GROWTH PHASE
1. PRIMEXINE MODEL
2. UNDULATION MODEL
• INTINE GROWTH PHASE
• REFERENCE
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3. • The wall of pollen is stratified.
• It comprises of two principle layer the inner
one celled intine and outer one celled exine.
• The exine consist of many sub layer.
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4. EXINE INTINE
EKTEXINE ENDEXINE
TECTUM BACULUM FOOT-LAYER
POLLEN WALL
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6. • It is composed of a class of material called
sporopollenin.
• It is derived from carotenoids by oxidative
polymerisation .
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7. • It is pecto-cellosic in nature.
• The cellulose component is microfibrillar.
• A special feature of the intine is the presence
of beads,ribbons,plate of enzymatic proteins
,particularly in the vicinity f the germ pores.
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10. • Pollen wall development may be considered
under exine and intine growth phases.
1. EXINE GROWTH PHASE
2. INTINE GROWTH PHASE
The pollen wall formation is discussed
under two models, viz., the primexine
model and the undulation model.
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13. 13

14. • A TEXTBOOK OF PALYNOLOGY-KASHINATH
BHATTACHARYA, MANAS RANJAN
MAJUMDAR, SWATI GUPTA BHATTACHARYA.
• PALYNOLOGY BY TAYLOR AND FRANCIS IN
1977.
• POLLEN AND SPORE MORPHOLOGY BY
G.ERDTMAN.
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