Final answer:
The human body is comprised of about 50-70% water, with infants having approximately 75% and the elderly as low as 45%. Water is crucial for various bodily functions and is present at different levels in various organs, the highest being in the brain and kidneys.
Step-by-step explanation:
The human body is an intricate system where water plays a critical role. Adult bodies are composed of about 50-70% water, which contributes to numerous physiological processes. Infants have a higher body water content, approximately 75%, while this percentage decreases with age, going as low as 45% in the elderly. The water content varies among different organs and tissues, with the brain and kidneys having the highest water composition at 80-85%, and teeth the lowest at 8-10%.
Water is indispensable to human functioning, acting as a major component of both intracellular and extracellular fluids. The transport of water amongst these compartments is regulated by osmosis, ensuring an appropriate balance of solutes for normal cell function. Overall, the understanding of water's role in the body is fundamental to grasping how our bodies maintain homeostasis and support life.