Preksha Dhyana Human Body Part 2

Author(s): Jethalal S Zaveri
Publisher: Jain Vishva Bharati

Page 85

Growth, Aging, Death
Growth
The life of a human, from conception to death, may be viewed as a continuous process-a series of events that follow one another in a programmed sequence, varying in details but leading to the same ultimate conclusion.
A living organism grows by the intake of food which is broken down into its constituent simpler substances which are then re-assembled into specific needs of the organism. Waste products are excreted, but the total of the materials, taken in, exceeds the amount returned to the environment, and there is a net increase in the size and weight of the organism. Cell-division--increasing the total number of cells—is the main process of growth.
Growth in size and weight, however, is not the whole story. The dramatic development of a fertilized ovum into a baby and that of a baby into an adult involve another improtant process, viz. differentiation-an increasing specialization of cells for specific functions. During childhood, the body and its parts only grow in size, but are constantly modified and reshaped permitting the mastery of new skills. During adult life, active growth ceases; cells that wear out or are destroyed by accident or disease are replaced and a dynamic equilibrium is maintained. But ultimately the repair processes become less efficient and cannot adequately réplace the day-to-day losses. Slowly various body-functions deteriorate.
Human growth is not a steady process. Dropping steadily throughout prenatal life, the rate of growth con
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