Finals - Cell Compounds

• How polarity in water molecule results in hydrogen bonding

  Each water molecule attracts other water molecules because of the opposite charges between them, forming hydrogen bonds
• Role of water as a solvent 


  Water is called the "universal solvent" because it is capable of dissolving more substances than any other liquid.

  Importance in life:

  1. Helps cells transport and use substances like oxygen or nutrients.
  2. Water-based solutions like blood help carry molecules to the necessary locations
• Role of water - Temperature Regulator


  Water in the body regulates the overall body temperature by helping dissipate heat.

  E.g. If the body becomes too hot, water is lost through sweat and the evaporation of this sweat from the skin surface removes heat from the body.
• Role of Water - Lubricant


  There is little friction between water molecules, making it an effective lubricant. Water reduces friction between joints and in body cavities.
• Distinguish acids, bases, and buffers

  Acids: dissociate into H+ and lower pH

  Bases: dissociate into OH– and raise pH

  Buffers: absorb these excess ions to maintain pH.
• Importance of pH to biological systems


  Cells and organisms must maintain a specific and constant pH in order to keep their enzymes in the optimum state of protonation