3.5.3 Energy And Ecosystems

Question 1

Why is bomb calorimetry preferable to simple calorimetry

Answer 1

Reduces heat loss to surroundings

Question 2

How could a student ensure all water had been removed from sample before weighing

Answer 2

Heat sample and reweigh until mass reading is constant

Question 3

Why is most of the Sun’s energy not converted into organic matter

Answer 3

Solar energy absorbed by atmosphere/reflected by clouds
Photosynthetic pigments can’t absorb some wavelengths of light
Doesn’t all fall directly on chlorophyll
Energy lost as heat during respiration

Question 4

Farming practices used to increase efficiency of energy transfer

Answer 4

Exclusion of predators
Artificial heating
Restriction of movement
Controlled feeding

Question 5

Why is a pyramid of biomass preferable to a pyramid of numbers

Answer 5

Shape of pyramid of numbers may be skewed since a small number of producers can support many consumers

Question 6

What is a pyramid of biomass

Answer 6

Diagram that shows the biomass at each trophic level