13.3 Development

• Development is a term that includes all changes that an organism goes through during its life cycle from germination of the seed to senescence
• Plants follow different pathways in response to environment or phases of life to form different kinds of structures. This ability is called plasticity,
• heterophylly is a type of plasticity
• In cotton, coriander and larkspur the leaves of the juvenile plant are different in shape from those in mature plants
• Difference in shapes of leaves produced in air and those produced in water in buttercup also represent the heterophyllous development due to environment
• Intrinsic factors include both intracellular (genetic) or intercellular factors (chemicals such as plant growth regulators)
• Extrinsic factors include light, temperature, water, oxygen, nutrition, etc.