5B Energy Transfers in Ecosystems

Question 1

Define ecosystem

Answer 1

all the organisms living in an area and the non living (abiotic) conditions

Question 2

Define producers

Answer 2

organisms which make their own food

Question 3

what are the sugars in respiration used for

Answer 3

growth and reproduction

Question 4

Define biomass

Answer 4

total mass of living organisms or the total chemical energy stored

Question 5

food chain

Answer 5

primary consumer -> secondary consumer -> tertiary consumer

Question 6

How to measure biomass using dry mass

Answer 6

Dry sample in oven and heat
After 24 hours record mass and reheat until a constant weight is recorded

Question 7

How to measure biomass using a calorimeter

Answer 7

Sample of biomass is burned and the energy released is used to heat a known volume of water. The change in temperature is used to calculate the chemical energy of the biomass

Question 8

Define gross primary production

Answer 8

total amount of chemical energy that is converted from light energy by plants

Question 9

Define respiratory loss

Answer 9

the amount of primary gross production that is lost in the environment as heat when plants respire

Question 10

Define net primary production

Answer 10

Remaining chemical energy after respiration as is available for growth and reproduction

Question 11

Net production of consumers equation

Answer 11

N= I - (F+R)
N - Net production
I - Chemical energy in ingested food
F - Chemical energy lost in faeces or urine
R - Energy lost through respiration