B1.5 Energy and Biomass in Food Chains Flashcards
What is biomass?
The mass of living material.
What happens to biomass as you move up the food chain?
As you move up the food chain, the amount of biomass decreases at each level.
How do you draw a pyramid of biomass?
Each trophic level of a food chain needs to have a separate bar. The size of the bars need to decrease towards the top of the pyramid and be drawn to scale. The order of the bars must match the order in the food chain and all the bars must be labelled
What is the source of energy at the start of most food chains?
Light energy from the sun.
What do green plants and algae do with the light energy from the sun?
They absorb some of the sun’s light energy and convert it into chemical energy when they photosynthesise.
What happens after green plants and algae photosynthesise?
They store chemical energy from photosynthesis in their cells.
How is energy passed from green plants and algae to animals?
Animals eat the green plants and algae.
What two things are lost at each stage of the food chain?
Biomass and energy.
Why are biomass and energy lost at each stage of the food chain? (3 reasons why)
Organisms respire and the energy released from respiration is used to fuel life processes or lost as heat. Not all parts of plants and animals, such as bones, can be eaten. Some energy is lost in waste products such as excretion of faeces or urine which aren’t usually eaten.
