FLOWER DEVELOPMENT : FLOWER DEVELOPMENT Presented by-LALAWMPUIA
Guide- JBN Slide 3: Flower – Sexual Reproductive Organs
Flower – Petals Sepals Stamen Carpels From Green Algae – Angiosperm 140 million years ago : From Green Algae – Angiosperm 140 million years ago Slide 5: Goethe (1790) believe that Flower are derived from Leaf Flowering step – Where??? : Flowering step – Where??? Apical meristem
Flower meristem on which flowers develop Slide 7: Apical meristem:
#Physiological changes occur at the shoot apical meristem (SAM).
#Cell division in the meristem is required to provide new cells for initiation of new organs, providing the Basic structure of the plant body. Organisation of an apical meristem
1 - Central zone
2 - Peripheral zone
3 - Medullary (i.e. central) meristem
4 - Medullary tissue Slide 9: Floral meristem
The shoot apical meristem is transformed into an inflorescence meristem which goes on to produce the floral meristem which produces the familiar sepals, petals, stamens and carpels of the flower Slide 10: Genes Genes Genes !!! THE POWER OF GENETICS : THE POWER OF GENETICS Stem cell Gene X(LEAFY,
CAULIFLOWER) Stem cell Mutant
Gene X Slide 12: Arabidopsis plant has flowers at many developmental stages Young flower Primodia : Young flower Primodia Sepals Petals Stamen Carpel How do cell on the outside know they should form the Sepals?????....... : How do cell on the outside know they should form the Sepals?????....... Sepal Stamen Carpel Homeotic Genes ABC Model of Flower Development : ABC Model of Flower Development The Flower Primodia is divided into four Concentric rings of cell (1,2,3,4).
These four rings define the four different type of Flower Organs that will later arise. ABC Model Of Organ Development : ABC Model Of Organ Development The A, B and C genes specify the four different organ types(Sepal, Petal, Carpel and Stamen).
Each of this Gene is active in two adjacent ring of cell. ABC Model : A = Sepals
A+B = Petals
B+C = Stamen
C = Carpels ABC Model Model describes the interactions of different genes that control floral organ identity Normal Flower : Normal Flower If all A,B&C Genes are mutated!!! : If all A,B&C Genes are mutated!!! Formation of numerous Leaves Slide 29: Goethe (1790) believe that Flower are derived from Leaf What about his Ideas???.......... Slide 30: What about Leaf to Flower ???....... NO Missing ???? Slide 31: D - Gene D - Gene D - Gene D - Gene Slide 37: What happen D Genes gets Mutated?????.. Slide 38: YES After introduction of D - Genes Slide 39: Thank YOU Slide 40: Thank You