2.4 water and its function

Question 1

draw the structure of water and include dipoles

Answer 1

page 48

Question 2

draw water molecules showing hydrogen bonding

Answer 2

page 48

Question 3

why is water having a high latent heat of vaporisation beneficial to multicellular organisms?

Answer 3

used to cool animal down when water evaporates

Question 4

what is latent heat of vaporisation?

Answer 4

energy required to evaporate 1 gram of water

Question 5

what is cohesion?

Answer 5

tendency of molecules to stick together

Question 6

why is water having a high cohesive force beneficial to multicellular organisms?

Answer 6

• plants can pull water up the xylem against gravity

- pond skaters can walk on water

Question 7

what is surface tension?

Answer 7

force which makes water moles be pulled back into the body of water rather than escaping from it

Question 8

5 important uses/ properties of water to living organisms

Answer 8

• water in metabolism
• water as a solvent
• evaporation cools down organisms
• not easily compressed to supports
• transparent

Question 9

which gases can dissolve in water?

Answer 9

• oxygen

- carbon dioxide

Question 10

which waste products can dissolve in water?

Answer 10

• ammonia

- urea

Question 11

what else can dissolve in water?

Answer 11

• inorganic ions
• small hydrophilic molecules
• enzymes

Question 12

why is it important that water is transparent?

Answer 12

aquatic plants can photosynthesise and aquatic animals can see

Question 13

uses of iron ions

Answer 13

• haemoglobin -> transport

Question 14

uses of phosphate ions

Answer 14

• DNA -> structural

- ATP -> energy storage

Question 15

uses of hydrogen ions

Answer 15

• pH -> determines structure of enzymes

Question 16

uses of sodium ions

Answer 16

• transport of glucose and amino acids across plasma membranes