Water

Question 1

Water

Answer 1

• medium for metabolic reactions
• is an important part of cells

Question 2

Charges of a water molecule

Answer 2

• no overall charge
• is a dipole, therefore has a positively charged end, hydrogen, and a negative charged end, oxygen.
• is a polar molecule (a molecule with separated charge)
• charges are very small and is written as a- on the oxygen, and a+ on the hydrogen, (in order to distinguish them from full charges)

Question 3

Water’s properties

Answer 3

• Is a solvent
  - dipoles so attract charged particles and other polar molecules
  
  • Which dissolve in water, for chemical reactions to happen.
• Acts as a median transport.
  - in animals plasma transports dissolved substances
  - in plants water transports minerals in the xylem
• Is a metabolite
  - is used in many biochemical reactions as a reactant e.g. in photosynthesis
  - many reactions use hydrolysis, and in condensation
• Has a high specific heat capacity
  - large amount of heat energy is needed to raise the temperature
  - large amount of hydrogen bonds need to be broken therefore large fluctuations in water is prevented
  - keeps aquatic habitats stable