Importance of Water in Living Organisms

Importance of Water in Living Organisms

• Water is the most abundant molecule in the body, making up 60% of an adult's body weight, and is essential for life.
• Water is a universal solvent, enabling easy interactions between molecules without forming strong ionic or covalent bonds.
• It is possible to survive without food for over a month, but dehydration can lead to death within a week.
• Water is a reactant and plays a crucial role in maintaining a stable pH and electrolyte balance.

Characteristics of Life

• Life is characterized by regular structure, reproduction, growth, response to environment, energy processing, regulation, and evolutionary adaptation.
• These characteristics are essential for life to exist and thrive.

Hierarchy of Life

• Biome: The entire ecosystem on Earth, including water, land, and air.
• Ecosystem: A specific region with all living organisms, water, land, and air.
• Community: All living organisms within an ecosystem.
• Population: A group of individuals of the same species.
• Organism: A single living being.
• Organ and organ systems: Functional units within an organism.
• Tissue: A group of similar cells.
• Cell: The basic unit of life.
• Organelle: A subcellular structure with specific functions.
• Molecule: A group of atoms.
• Atom: The smallest unit of matter.

Molecular Composition of the Body

• In a 65 kg person, the body composition is:
  • Water: 61.6% (40 kg)
  • Protein: 17.0% (11 kg)
  • Lipid: 13.8% (9 kg)
  • Minerals: 6.1% (4 kg)

Elemental Composition of the Body

• Macro elements: O, C, H, N, Ca, P, K, S, Na, Cl, Mg
• Micro elements (trace elements): essential for bodily functions, but present in small amounts

Learn about the essential role of water in living organisms, its functions, and why it's crucial for life. Understand its importance in maintaining pH and electrolyte balance.