Every human being begins his/her life as a single cell – the fertilized ovum. The cell undergoes division, growth, differentiation and development through the stages of embryo, fet us, infant, child and adult. This process goes on under the influence of environment and genetic traits from the parents. As we learnt in the earlier units, it is clear that although growth and development may occur simultaneously both are distinct biological processes. Growth and development is the progression by which human advances biologically from conception to death.
In common terms growth refers to an increase in size of the body as a whole or that of a specific body part. For example when we talk of children growing, it means that they are becoming taller and heavier and their organs are increasing in size. Development signifies a broader concept- the differentiation and specialization of various tissues and body parts of embryo and fetus. Development also means increased complexity in thought, behavior, skill, or even function.