Water

• How does water help in the transport of substances?


  • Transports nutrients, gases, and wastes
  • Acts as a lubricant in joints and organs
• What role does water play in chemical reactions?


  • Medium for biochemical reactions
  • Reactant in hydrolysis and dehydration synthesis
• How does water contribute to cooling in organisms?


  • Evaporation of sweat removes excess heat
  • High heat of vaporization makes it effective
• What is the role of water in excretion?


  • Removes waste products like urea
  • Facilitates elimination of toxins
• How does water support living environments?


  • Provides homes to diverse organisms
  • Supports ecosystems with stable conditions
• What is the significance of turgor pressure in plants?


  • Maintains structure of plant cells
  • Essential for growth and rigidity
• Why is water considered a universal solvent?


  • Dissolves ions and polar molecules
  • Facilitates transport and reactions
• What role does water play in photosynthesis?


  • Raw material in photosynthesis
  • Splits into oxygen, protons, and electrons
• How does ice benefit aquatic life in cold climates?


  • Ice floats, insulating aquatic life
  • Prevents entire water bodies from freezing
• What is the role of water in hydrolysis reactions?


  • Breaks down large molecules into smaller units
  • Essential for digestion and metabolism
• How does water act as a temperature buffer in aquatic habitats?


  • High specific heat capacity stabilizes temperatures
  • Protects organisms from extreme fluctuations
• What is the significance of cohesion and surface tension in water?


  • Enables capillary action in plants
  • Supports small organisms on water surfaces
• Why is water vital for life?


  • Integral to metabolism, structure, and environment
  • Essential for ecological balance
• What is the structure of a water molecule?


  • One oxygen atom bonded to two hydrogen atoms
  • The molecule has no overall charge
• Why does the oxygen atom in water have a slight negative charge?


  • Oxygen is more electronegative than hydrogen
  • Pulls shared electrons closer to itself
• Why do hydrogen atoms in water have a slight positive charge?


  • Electrons are pulled towards oxygen
  • Leaves hydrogen atoms with a slight positive charge
• What does the symbol δ represent in water molecules?

  • Indicates a slight charge on atoms
  • δ- for oxygen and δ+ for hydrogen
• What causes hydrogen bonds to form between water molecules?

  • Attraction between slightly positive hydrogen and slightly negative oxygen
• What unique properties of water are due to hydrogen bonding?

  • Cohesion, high surface tension, high specific heat capacity
  • Role as a solvent
• Why is water considered a polar molecule?


  • Uneven distribution of charge
  • Oxygen is slightly negative and hydrogen is slightly positive
• What does it mean that hydrogen bonds are "transient"?


  • Easily made and broken
  • Allows water to adapt its structure dynamically
• How do hydrogen bonds affect the state of water at normal temperatures?


  • Keeps water liquid at normal temperatures
  • Unlike other similar-sized molecules that are gases
• Why does water have a high specific heat capacity?


  • Numerous hydrogen bonds require a lot of energy to break
  • Stabilizes temperatures in aquatic habitats
• What is the importance of water's high latent heat of evaporation?

  • Takes a lot of energy for water to evaporate
  • Effective cooling mechanism through sweating and panting
• How does hydrogen bonding contribute to water's cohesion?

  • Water molecules stick together due to hydrogen bonds
  • Aids in transpiration and creates surface tension
• Why is water a good solvent for ionic compounds?

  • Polarity allows it to dissolve ionic compounds
  • Ideal for chemical reactions and transport
• How does hydrogen bonding affect water’s structure when it freezes?

  • Aligns water molecules into a crystal lattice
  • Makes ice less dense than liquid water
• Why is the density of ice important for aquatic organisms?

  • Ice floats, insulating water beneath
  • Provides habitat and prevents freezing
• Transport of substances and lubricant


  • Water helps transport nutrients, gases, and wastes in organisms (e.g., blood in animals, sap in plants).
  • Acts as a lubricant in joints (synovial fluid) and around organs.
• Chemical reactions (metabolism)


  • Water is a medium for most biochemical reactions.
  • Reactant in hydrolysis and dehydration synthesis.
• Cooling (sweating)


  • Evaporation of sweat removes excess heat.
  • High heat of vaporization makes it an effective cooling agent.
• Excretion


  • Water helps remove waste products like urea (via urine).
  • Facilitates the elimination of toxins.
• Excretion


  • Water helps remove waste products like urea (via urine).
  • Facilitates the elimination of toxins.
• Support in plant tissues (turgor)


  • Turgor pressure in plant cells maintains structure.
  • Essential for growth and rigidity.
• Solvent


  • Water dissolves ions and polar molecules, facilitating transport and reactions.
  • Universal solvent due to polarity.
• Photosynthesis


  • Water is a raw material in photosynthesis.
  • Splits into oxygen, protons, and electrons during light reactions.
• Insulating ponds

  • Ice floats due to lower density, insulating aquatic life in cold climates.
  • Prevents entire water bodies from freezing.
• Hydrolysis reactions


  • Water breaks down large molecules into smaller units (e.g., proteins into amino acids).
  • Essential for digestion and metabolism.
• Temperature buffer in aquatic habitats


  • High specific heat capacity stabilizes temperatures in aquatic environments.
  • Protects organisms from extreme temperature fluctuations.
• Cohesion and surface tension

  • Water molecules stick together (cohesion), enabling capillary action in plants.
  • Surface tension supports small organisms like insects on water surfaces.