chemistry of life

• inorganic compounds:

  • these compounds do not contain the element carbon 12
  • examples: water, carbon dioxide and mineral salts
• Minerals

  • are inorganic substances that are required by living organisms
  • There are two groups micro elements and macro elements (small and big quantities)
• Functions of water:

  • used during digestion to break down large insoluble substances into smaller soluble substances
  • it is a medium for all chemical reactions in the cell
  • it is used to transport food along the alimentary canal and mineral salts in plants
  • it dissolves the waste substance in the body to form urine and sweat
• The need for fertilizer in over used soil:

  • synthetic fertilizers are used to replace lost nutrients (nitrogen, phosphorus and potassium)
  • When it rains these fertilizers may be washed out into the rivers
  • the nutrient content of the water will increase
  • the increased nutrient content causes a rapid growth of plant and algae in the water
  • This is called eutrophication
• The need for fertilizer in over used soil:

  • increased plant growth especially the algae covers the surface of the water, preventing sunlight from reaching the plants lower down in the water
  • the plants will die and the aquatic organisms that depend on these plants will also die
  • the dead plant and animal matter will begin to rot and attract bacteria to the water
  • this increased bacteria uses more oxygen and this decreases the oxygen content of water
  • this results in more plants and animals dying
• Solute


  A substance that is dissolved in a solvent to form a solution
• Solute


  • salt in water
  • sugar in tea
• Solvent


  The substance in which the solute is dissolved to form a solution
• Solvent


  • water
• Solution


  A homogeneous mixture composed of two or more substances, where a solute is dissolved in a solvent
• Solution


  • saltwater
  • sugar water
• Osmosis


  The movement of water molecules through a semi-permeable membrane from a region of lower solute concentration to a region of higher solute concentration, aiming to equalize the solute concentrations on both sides of the membrane
• Water Potential Gradient


  The difference in water potential (potential energy of water) between two regions. Water moves from a region of higher water potential to a region of lower water potential
• Hypotonic


  A solution with a lower concentration of solutes compared to another solution. Cells in a hypotonic solution tend to swell as water enters the cell
• Isotonic


  A solution with the same concentration of solutes as another solution. Cells in an isotonic solution maintain their normal shape and function because there is no net movement of water
• Hypertonic


  A solution with a higher concentration of solutes compared to another solution. Cells in a hypertonic solution tend to shrink as water leaves the cell
• Uses of Water

  1. Drinking and Hydration

  • Essential for maintaining bodily functions and overall health.

  2. Agriculture

  • Irrigation for crops and livestock hydration.

  3. Industrial Uses

  • Cooling machinery, processing, and manufacturing.

  4. Sanitation

  • Washing, cleaning, and waste removal.

  5. Cooking

  • Ingredient and medium for preparing food.

  6. Recreation

  • Swimming, boating, and other water sports.

  7. Environmental

  • Habitat for aquatic life and maintaining ecosystems.

  8. Energy Production

  • Hydroelectric power generation.