M1:01a Water

Question 1

Name the functions of water in living organisms in terms of metabolism

Answer 1

-used to break down many complex molecules by hydrolysis.- chemical reactions take place in an aqueous medium eg cytoplasm- major raw material in photosynthesis

Question 2

Name the functions of water in living organisms in terms of a solvent

Answer 2

its readily dissolves other other substances and is used for transport, removal of wastes, and secretions.

Question 3

Give an example of how water is used as transport

Answer 3

blood plasma

Question 4

Give an example of how water is used for removing waste

Answer 4

ammonia / urea

Question 5

Give an example of how water is used as secretions

Answer 5

digestive juices / tissues

Question 6

Name the functions of water in living organisms in terms of lubricants

Answer 6

mucus to aid external movement eg in the gut/ an earthworm moving through the soil -fluids to reduce friction, eg synovial fluids in joints, pleural fluid round the lungs and the perivisceral fluid around internal organs.

Question 7

Name the functions of water in living organisms in terms of giving support

Answer 7

water isnt easily compressed, so is used in the hydrostatic skeleton of animals such as earth worms, the amniotic fluid to support the fetus, creates turgor pressure that supports the leaves of the plants.

Question 8

Name the functions of water in living organisms.

Answer 8

• evaportation ciiks irganisms and allows them to control their temperatures transparent so aquatic plants can photosynthesise.

Question 9

Name the properties of water

Answer 9

-dipolar -water and hydrogen bonding-specific heat capacity of water-latent heat of vaporisation of water-cohesion and surface tension-density of water -good solvent-allows animals to sweat (high latent heat vaporisation)

Question 10

Why is water so important as an enviroment for living organisms

Answer 10

-it minimizes temperature fluctuations due to its high specific heat capacity-its transparent, so aquatic organisms can see/photosynthesise.-It has a high tension surface for pondskaters-ice is less dense than water so floats, protection layer, by isolation and preventing it from freezing completely , creates nutrient cycle in lakes-high density, organisms need to be stream lined.