The specific series of changes by which cells form tissues, organs, and organisms is called development. Development unfolds according to the genetic information that an organism inherits from its parents but is also influenced by the external environment.
A single genotype can produce different phenotypes in different environments. For example, the aquatic plant called the fanwort (Cabomba caroliniana) forms two very different types of leaves, depending on whether or not the shoot apical meristem is submerged. This ability to alter form in response to local environmental conditions is called developmental plasticity. Dramatic examples of plasticity, as in Cabomba, are much more common in plants than in animals and may help compensate for plants’ inability to escape adverse conditions by moving.
In development, the three overlapping processes are growth, morphogenesis, and cell differentiation.
Growth is an irreversible increase in size. Morphogenesis (from the Greek morphê : shape, and genesis: creation) is the process that gives a tissue, organ, or organism its shape and determines the positions of cell types. Cell differentiation is the process by which cells with the same genes become different from one another.