2.4- Water and it's functions

Question 1

Properties of water

Answer 1

1. High specific heat capacity- acts as a buffer against sudden temperature changes in organisms
2. High latent heat of vaporisation- sweating is an effective cooling method for organisms
3. Cohesion- hydrogen bonding leads to large cohesive forces which allow water to be pulled through a tube

Question 2

water in metabolism

Answer 2

• used in hydrolysis and condensation reactions
• chemical reactions take place in aqueous medium
• water used in photosynthesis

Question 3

water as a solvent

Answer 3

• carbon dioxide and oxygen
• wastes such as urea and ammonia
• inorganic ions and small hydrophilic molecules
• enzymes, whose reactions take place in solution

Question 4

other important features of water

Answer 4

• its evaporation allows organisms to control their temperature and cool themseleves
• not easily compressed so provides support
• transparent allowing aquatic plants to photosynthesise