Final answer:
A child's body is composed of approximately 75% water, which decreases to about 50-60% in adults. Water is essential for bodily functions and is distributed throughout various organs and tissues.
Step-by-step explanation:
The body water content of a child's body is composed of approximately 75 percent water. Infants have about 75% of their body mass as water, but this percentage decreases as people age. Adults typically have about 50-60% water in their bodies. Water is crucial for various functions, such as forming the environment for biochemical reactions and facilitating the transportation of nutrients and waste. It is distributed throughout the body's cells, tissues, and organs. The high percentage of water is present in infants because the proportions of the body dedicated to each organ, as well as to muscles, fat, bone, and other tissues, change from infancy to adulthood.