1. The Genetic Basis of Growth and Development

2. Plants are made up of cells tissues organs

5. Plants have specialized tissues called meristems Shoot apical meristem (SAM) Intercalary meristem Root apical meristem (RAM) Lateral meristems: pericycle, vascular cambium

6. Plants grow by cell division expansion differentiation

7. Plant development is controlled by hormones Auxin:stimulates growth and cell division Gibberellins:stimulates stem growth and seed germination Cytokinins:regulates cell division and senescence Abscisic Acid:responds to osmotic stress, inhibits germination, closes guard cells

8. More Hormones Ethylene:regulates fruit ripening and flowering, responds to stress Jasmonic Acid:responds to insect attacks turning on plant defenses Brassinosteroids: affect stem elongation, pollen tube growth, leaf bending and xylem differentiation

9. Plant development is affected by the environment Phototropism (light) Gravitropism (gravity) Thigmotropism (touch) Nyctinastic movement (light) Thigmonastic movement (mechanical)

10. Environmental Influences Circadian Rhythms (biological clocks set by light) Dormancy (temperature, light & water) Vernalization (cold induction of flowering) Stratification (cold induction of germination) Photoperiodism (germination and flowering)

11. Photoperiodic regulation of flowering

12. Genetic control of flowering

13. Signal transduction by hormones or environmental signals

14. Genetic modification can redirect developmental processes Male sterility for hybrid seed production Fruit ripening Senescence Delaying seed pod splitting Flowering