What factors affect the rate of decay?
Temperature, water and oxygen
Temperature, water and light
Temperature, light and wind strength
Where have we found very old, naturally preserved skeletons?
In Egyptian tombs
Peat bogs
Graves
What is compost made from?
Animal faeces
Manure
Dead plants
Which element is required to make protein?
Nitrogen
Magnesium
Iodine
What does anaerobic mean?
In the presence of oxygen
Without oxygen
Without air
What gases make up biogas?
Methane and ethanol
Propane and carbon dioxide
Methane and carbon dioxide
What effect does lowering temperature have on the decay of milk?
It slows it down
No effect
It speeds it up
Why does the pH of milk reduce when it decays?
Glucose is converted to lactic acid
Lactose is converted to lactic acid
Glucose is converted to carbon dioxide and water
How do we calculate the rate of change from values?
Vertical change divided by horizontal change
Change in time divided by change in value
Change in value divided by change in time
How do we calculate the rate of change from a graph?
Horizontal change divided by vertical change