water

Question 1

explain five properties that make water important for organisms. (5)

Answer 1

1. metabolite in condensation/hydrolysis/photosynthesis/respiration;
2. a solvent so (metabolic) reactions can occur;
3. high specific heat capacity so buffers changes in temperature;
4. large latent heat of vaporisation so provides a cooling effect (through evaporation);
5. cohesion (between water molecules) so supports columns of water (in plants);
6. cohesion (between water molecules) so produces surface tension supporting (small) organisms;

Question 2

state and explain the property of water that helps to prevent temperature increase in a cell.

Answer 2

1. high (specific) heat capacity;
2. buffers changes in temperatures;

Question 3

state and explain the property of water that can help to buffer changes in temperature. (2)

Answer 3

1. (water has a relatively) high (specific) heat capacity;
2. can gain/lose a lot of heat/energy without changing temperature;
   OR
   takes a lot of heat/energy to change temperature;

Question 4

water and inorganic ions have important biological functions within cells.
give two properties of water that are important in the cytoplasm of cells. for each property of water, explain its importance in the cytoplasm. (4)

Answer 4

1. polar molecule;
2. acts as a (universal) solvent;
   OR
3. (universal) solvent;
4. (metabolic) reactions occur faster in solution;